magic
magic - trick with water and ice. How did I do that?
Trick with predicting a card. How did I do that?
Magic and science.
disappearing rabbit trick. Make something a kid has disappear. have them bark like a dog. Clap.
How does this work?
The trick thumb. Make a piece of paper vanish. Make a handkerchief appear.
kid lie on floor, hold arms over head, explain sensation. slowly lower kid's arms... tell me to stop when you think it will touch the floor.
Magic floating arm.
hydrophobic sand (can do with matches)... you can use baby powder to do this at hime.
3 cup monte with hydrophilic gel. Dissect a diaper.
Ninja popsicle sticks
====
Pick a number, any two digit number will do.
Add the two digits together and then subtract the total from the original number.
The result will always be a multiple of nine, so adding the digits of your answer will always result in the number nine.
38=11=27/3(first number)=9
96=15=81/8=9
This trick begins with a stacked deck! Separate the Aces and Kings from an ordinary poker deck. Place the 4 Aces on top of the other cards. Place the Kings on top of the Aces. Kings are now uppermost in the deck.
Find a volunteer and say something like: "You look like you can deal out a mean hand of cards! Please take this pack and deal out two piles, alternating cards."
Let them deal about half of the deck and then say: "You may stop anytime you wish". Take the undealt deck of cards and place them aside.
Say to your volunteer: "Now, please pick up one of those two piles and deal it into two smaller piles. Do the same with the other pile so that we will end up with 4 piles of cards."
At this point there will be a king on the top of every deck.
"Turn up the top of any pile. Oh....that's a king. Turn over another - another king! Coincidence. Yet another and another."
Once the volunteer has turned up all 4 kings discard them.
"Anyone here a poker player? What beats four kings? Why.....four ACES, right"
Make some magical passes of your hand over the four piles. Turn up the top card of each pile to reveal ACES
Monday, October 26, 2009
Static Electricity experiments
------------------ static electricity
* A balloon
* A clean head of hair
* Some tiny bits of torn up newspaper
* A sheet of aluminum foil about 1 foot long
* A wool sweater or sock
* A sheet of wax paper about 1 foot long
* A sheet of cellophane wrap about 1 foot long
Begin by blowing up the balloon and rubbing it on your head. What happens to your hair? Now lay the bits of paper out on a table in front of you. Bring the balloon near, but don't actually touch the paper. What happens?
Straw Exercise
Carefully tear one end of the paper and slide about one inch of the straw out of the paper. Rub the straw in and out of the paper for 5-10 seconds. Remove the paper and lay it on the table while hoding one end of the straw with your fingertips. Like a wand, lower the straw and hold it next to the paper, then raise the straw. What does the paper do?
* A balloon
* A clean head of hair
* Some tiny bits of torn up newspaper
* A sheet of aluminum foil about 1 foot long
* A wool sweater or sock
* A sheet of wax paper about 1 foot long
* A sheet of cellophane wrap about 1 foot long
Begin by blowing up the balloon and rubbing it on your head. What happens to your hair? Now lay the bits of paper out on a table in front of you. Bring the balloon near, but don't actually touch the paper. What happens?
Straw Exercise
Carefully tear one end of the paper and slide about one inch of the straw out of the paper. Rub the straw in and out of the paper for 5-10 seconds. Remove the paper and lay it on the table while hoding one end of the straw with your fingertips. Like a wand, lower the straw and hold it next to the paper, then raise the straw. What does the paper do?
Monday, September 28, 2009
taste
What's your favorite food?
* sweet
* sour
* salty
* bitter
Have counter count how many people like each.
Have counter count qualities.
Going to be looking at taste. Will be using flavors on a cotton swab... don't mix and don't share.
Have four students demo how the taste test is done and how it's mapped. These become helpers at stations.
Can you taste the same thing in all areas of the tongue? Sweet, salty, sour, bitter. Bumps on tongue are taste buds and some get replaced every 24 hours! It was once thought that you could taste things only in one area. Is this true?
bitter medicine -- people spit it out. If you put sugar in, is the bitter still there? Why would they tell us to put aspirin on the front of the tongue before swallowing it?
food coloring... paint your tongue front with blue food coloring. Place wax paper on tip of tongue. Count the number of unstained circles. the more of those you have the more fungiform tastebuds you have. This is why some people can't eat certain foods. Changes as you get older.
Perfumes (which is which?) artificial flavor.
Smell-a-drink (coke and pepsi and diet coke) Which is which?
making gum drops?
Nose pinch and blindfolded smell of coke and pepsi and diet coke.
* sweet
* sour
* salty
* bitter
Have counter count how many people like each.
- What are the four familiar tastes?
- What part of the body do we use to taste?
- Fifth flavor, "Umami." Cheese is an example of Umami.
- other things about food -- spicy, temperature, color, smell
Have counter count qualities.
Going to be looking at taste. Will be using flavors on a cotton swab... don't mix and don't share.
Have four students demo how the taste test is done and how it's mapped. These become helpers at stations.
Can you taste the same thing in all areas of the tongue? Sweet, salty, sour, bitter. Bumps on tongue are taste buds and some get replaced every 24 hours! It was once thought that you could taste things only in one area. Is this true?
- Using your map, point to the places on your tongue where you would most likely taste a candy bar, potato chips, lemon juice, and a grapefruit peel.
bitter medicine -- people spit it out. If you put sugar in, is the bitter still there? Why would they tell us to put aspirin on the front of the tongue before swallowing it?
- What does the sense of taste teach you about the world we live in?
- How does taste help us select and enjoy food?
- What would happen to you without the sense of taste?
food coloring... paint your tongue front with blue food coloring. Place wax paper on tip of tongue. Count the number of unstained circles. the more of those you have the more fungiform tastebuds you have. This is why some people can't eat certain foods. Changes as you get older.
- Describe how the sense of taste and the sense of smell are related.
- What are some things that should not be tasted
Perfumes (which is which?) artificial flavor.
Smell-a-drink (coke and pepsi and diet coke) Which is which?
making gum drops?
Nose pinch and blindfolded smell of coke and pepsi and diet coke.
Forces
note: if class is small, divide into stations. For largest class, demonstrations. Bring tops.
Forces make stopped objects move and moving objects stop.
Have two volunteers jump. What made them come down? What made them go up (prompt for muscles)? Drop pencil. What made it fall?
Catapult... what made ball fly?
bouncing ball... what happens when it bounces? bounce clay. Now what do you think happens? Push in ball -- what happens to surface? Push in clay? How does ball act like muscles?
"Center of gravity"... what does that sound like? Place where things balance.
Put hat and string on someone's head. have them stand with legs apart. Where is center of gravity? Now stand on one leg. Where is it?
partner control -- have two kids. Ones sits on chair other puts thumb against first one's forehead. try to stand up. What happened with center of gravity?
have child prove they can bend to pick up pencil. Now, stand with toes to wall. Take 3 toe-heel steps back. pick up a pencil (they can't). What happened with center of gravity when you stick your hips way out?
Balance an improbable object with pencils (ball of clay on fork) How did that change center of gravity?
gyroscopes and tops -- precession causes motion in a circle. What makes a good top? How could I turn clay into top?
Gyroscope and bike wheel
coke bottle demo
Hot wheels roller coaster (but only use kids who have earned tokens)
Penny inside a balloon -- spinning things change their behavior. Throw balloon with spinning penny. What happened?
Forces make stopped objects move and moving objects stop.
Have two volunteers jump. What made them come down? What made them go up (prompt for muscles)? Drop pencil. What made it fall?
Catapult... what made ball fly?
bouncing ball... what happens when it bounces? bounce clay. Now what do you think happens? Push in ball -- what happens to surface? Push in clay? How does ball act like muscles?
"Center of gravity"... what does that sound like? Place where things balance.
Put hat and string on someone's head. have them stand with legs apart. Where is center of gravity? Now stand on one leg. Where is it?
partner control -- have two kids. Ones sits on chair other puts thumb against first one's forehead. try to stand up. What happened with center of gravity?
have child prove they can bend to pick up pencil. Now, stand with toes to wall. Take 3 toe-heel steps back. pick up a pencil (they can't). What happened with center of gravity when you stick your hips way out?
Balance an improbable object with pencils (ball of clay on fork) How did that change center of gravity?
gyroscopes and tops -- precession causes motion in a circle. What makes a good top? How could I turn clay into top?
Gyroscope and bike wheel
coke bottle demo
Hot wheels roller coaster (but only use kids who have earned tokens)
Penny inside a balloon -- spinning things change their behavior. Throw balloon with spinning penny. What happened?
Tuesday, September 15, 2009
Dry Ice
Set up:
Make sure there's some space between kids, have them work in pairs.
Make sure there's warm water around (pitcher of water)
If you have a chance, put a spoon in the warm water while you take roll, etc.
Get attention of kids, give them rules, introduce yourself.
explain that we are going to play with something that most kids never get to touch. Drop dry ice (use spoon) in a glass of water, and sip it as it foams. Tell them that at the end they will get to try the same kind of drink for themselves. Pour some of the fog on a kid's head.
Mention that dry ice "sublimes" (turns into gas, not liquid) as it melts. Tell them you can demonstrate it (put warm spoon on a large chunk of dry ice. Press firmly. Let them hear it "sing."
Show how cold it is by putting water in teaspoon and count seconds until it freezes.
Give them water with a little bit of soap in it, let them play with the bubbles.
Make "fizzy drink"
Put the last of the dry ice in warm water, let them sit around fog, try to corral it. Talk about Halloween special effects.
Give teams a cup (or container) for water and straw
Make sure there's some space between kids, have them work in pairs.
Make sure there's warm water around (pitcher of water)
If you have a chance, put a spoon in the warm water while you take roll, etc.
Get attention of kids, give them rules, introduce yourself.
explain that we are going to play with something that most kids never get to touch. Drop dry ice (use spoon) in a glass of water, and sip it as it foams. Tell them that at the end they will get to try the same kind of drink for themselves. Pour some of the fog on a kid's head.
Mention that dry ice "sublimes" (turns into gas, not liquid) as it melts. Tell them you can demonstrate it (put warm spoon on a large chunk of dry ice. Press firmly. Let them hear it "sing."
Show how cold it is by putting water in teaspoon and count seconds until it freezes.
Give them water with a little bit of soap in it, let them play with the bubbles.
Make "fizzy drink"
Put the last of the dry ice in warm water, let them sit around fog, try to corral it. Talk about Halloween special effects.
Give teams a cup (or container) for water and straw
Sunday, September 13, 2009
Classic slime
What you need:
pour the glue into the jar. Add 1/2 cup of water (if you're feeling lazy, just empty the glue bottle and then fill it with water and mix in there. Add coloring.
Mix 1 tsp of borax into 1 cup of water. Slowly stir the glue-water into the borax-water mix (note... this makes a LOT of slime. You can make small amounts of it at a time, however)
For kids, pour it into a ziplock bag and have them knead the bag until the slime forms. The more that it's worked, the firmer it becomes. Store the slime in this bag in the refrigerator to prevent mold.
Slime Fun:
Do a "slime drop." (does it fall all at once or stretch? Whose falls slowest?)
What happens if you pull it apart really fast?
What happens when you pull it apart slowly?
Do "whose slime stretches farthest" race and "who has chunkiest slime".
Have them name their slime.
- borax powder (20 Mule Team borax is what I use)
- water
- 4 ounces glue (that's 1/2 cup. Use Elmer's white glue or the blue school glue White makes opaque slime)
- teaspoon
- bowl
- jar or measuring cup
- food coloring (optional)
- measuring cup
pour the glue into the jar. Add 1/2 cup of water (if you're feeling lazy, just empty the glue bottle and then fill it with water and mix in there. Add coloring.
Mix 1 tsp of borax into 1 cup of water. Slowly stir the glue-water into the borax-water mix (note... this makes a LOT of slime. You can make small amounts of it at a time, however)
For kids, pour it into a ziplock bag and have them knead the bag until the slime forms. The more that it's worked, the firmer it becomes. Store the slime in this bag in the refrigerator to prevent mold.
Slime Fun:
Do a "slime drop." (does it fall all at once or stretch? Whose falls slowest?)
What happens if you pull it apart really fast?
What happens when you pull it apart slowly?
Do "whose slime stretches farthest" race and "who has chunkiest slime".
Have them name their slime.
Growing cyrstal gardens
A fun project to do in class over the period of a week or so is grow crystals. Here's one of the "classic" recipes:
Crystals will begin to grow in four hours and can continue growing for up to three days, depending on other conditions. Add more solution to keep them growing for a bit longer.
- substrate.
- 4 tbsp. bluing (found in grocery stores)
- 4 tbsp. salt (any kind)
- 1 tbsp. ammonia
- 4 tbsp. water
- food coloring
- plastic bowl or plate
Crystals will begin to grow in four hours and can continue growing for up to three days, depending on other conditions. Add more solution to keep them growing for a bit longer.
Tuesday, August 04, 2009
Detective Scavenger Hunt
Only do this in an area where you can have good control over the kids (noise and damage -- and make sure they can't injure themselves. Warn them away from or block off areas where things could be damaged.)
If you don't have time to make up a scavenger hunt list before the kids show up, hide a few things around the room and divide the group into teams. Have each team make a list of things for the other teams to find. Pull all of them out of the room and give each team (or person, if the group is small enough) an additional item to hide. Add that to the list.
Swap lists.
Turn them loose.
This can also be done to good effect with outdoor activities (make a rubbing of a leaf shaped like an arrowhead, find a bird, find an oak tree, etc)
If you don't have time to make up a scavenger hunt list before the kids show up, hide a few things around the room and divide the group into teams. Have each team make a list of things for the other teams to find. Pull all of them out of the room and give each team (or person, if the group is small enough) an additional item to hide. Add that to the list.
Swap lists.
Turn them loose.
This can also be done to good effect with outdoor activities (make a rubbing of a leaf shaped like an arrowhead, find a bird, find an oak tree, etc)
Tuesday, July 07, 2009
Using a rubric
Here's a nice page on using rubrics in teaching, something that can be added to a summer camp activity or any of the kits: http://www.learnnc.org/lp/pages/3735
In a nutshell, when doing something comparative, have the students list for you words that exemplify the quality of something (for example -- slime. You might pick "gooeyness" and "color" and "stickiness") and then judge a sample on a scale of 1 to 5. Everyone can pick a number; add them all together and divide by the number of people (to make it easy on yourself if you have an impatient class, divide the class and have one group judge on one attribute and another judge on a different attribute. YOU do the math, or hand someone a calculator and ask them to do it.)
Rubrics can be used as a starting point for a discussion in many different areas.
In a nutshell, when doing something comparative, have the students list for you words that exemplify the quality of something (for example -- slime. You might pick "gooeyness" and "color" and "stickiness") and then judge a sample on a scale of 1 to 5. Everyone can pick a number; add them all together and divide by the number of people (to make it easy on yourself if you have an impatient class, divide the class and have one group judge on one attribute and another judge on a different attribute. YOU do the math, or hand someone a calculator and ask them to do it.)
Rubrics can be used as a starting point for a discussion in many different areas.
Monday, June 22, 2009
Potato/tomato/lemon/vinegar battery
There's a number of videos on this activity that you can find through Google. Unfortunately, given the nature of video, they often vanish mysteriously into the bit bucket. And you can't give them a 20-second "look over" to refresh your knowledge; usually you have to sit there through the whole production.
So here's about making batteries from unusual things.
* it takes some sort of acid in solution. You might be able to do it with unusual things like aspirin diluted in water because (according to internet sources... we all know how reliable those are...) UNbuffered aspirin can be used to temporarily "revitalize" a dead battery. I'll try it sometime. Meanwhile, other things you can make batteries from (in case you forgot to buy a potato for the demonstration) include vinegar, lemon juice, and cola.
* you need an electrode of copper and one of zinc. A nail (zinc coated) and copper wire (or a penny) work well for this. You could use silver instead of copper, but that's more expensive.
* make sure the "leads" are clean. A little scrub with an abrasive works.
* if you're not using a vegetable or fruit, get a small container for the liquid.
* the amounts of electricity produced are small.
* use them to power a small LED. Look for one (Fry's) that doesn't require a lot of voltage.
http://www.physics.gla.ac.uk/~kskeldon/PubSci/exhibits/E1/
http://hilaroad.com/camp/projects/lemon/calculator/calculator_battery.html
If you think you've got kids who may have seen potato/lemon/tomato batteries before, provide them with a little novelty. Using oranges or cola (or unbuffered aspirin if it works) will provide the "say WHAT?" factor that keeps them intrigued.
You will connect the battery components in series, not parallel, if you want to try and power a light:
http://www.sierranevadaairstreams.org/owners-guide/understanding/battery-config.html
http://www.zbattery.com/Connecting-Batteries-in-Series-or-Parallel
So here's about making batteries from unusual things.
* it takes some sort of acid in solution. You might be able to do it with unusual things like aspirin diluted in water because (according to internet sources... we all know how reliable those are...) UNbuffered aspirin can be used to temporarily "revitalize" a dead battery. I'll try it sometime. Meanwhile, other things you can make batteries from (in case you forgot to buy a potato for the demonstration) include vinegar, lemon juice, and cola.
* you need an electrode of copper and one of zinc. A nail (zinc coated) and copper wire (or a penny) work well for this. You could use silver instead of copper, but that's more expensive.
* make sure the "leads" are clean. A little scrub with an abrasive works.
* if you're not using a vegetable or fruit, get a small container for the liquid.
* the amounts of electricity produced are small.
* use them to power a small LED. Look for one (Fry's) that doesn't require a lot of voltage.
http://www.physics.gla.ac.uk/~kskeldon/PubSci/exhibits/E1/
http://hilaroad.com/camp/projects/lemon/calculator/calculator_battery.html
If you think you've got kids who may have seen potato/lemon/tomato batteries before, provide them with a little novelty. Using oranges or cola (or unbuffered aspirin if it works) will provide the "say WHAT?" factor that keeps them intrigued.
You will connect the battery components in series, not parallel, if you want to try and power a light:
http://www.sierranevadaairstreams.org/owners-guide/understanding/battery-config.html
http://www.zbattery.com/Connecting-Batteries-in-Series-or-Parallel
Saturday, May 16, 2009
Keeping them amused in the morning
Papercraft (you print out 10 pieces of paper, bring scissors, glue, let them have at it usually does 2 things -- they're interested in a build and are learning build skills and they're keeping quiet.
A few for you to look at:
robots:
http://members.chello.nl/m.egtberts2/pdf/retrobot.pdf
Color their own/make their own:
http://members.chello.nl/m.egtberts2/pdf/fs_blank.pdfhttp://thunderpanda.com/509/
Thunderpanda Troops:
http://thunderpanda.com/509/
A few for you to look at:
robots:
http://members.chello.nl/m.egtberts2/pdf/retrobot.pdf
Color their own/make their own:
http://members.chello.nl/m.egtberts2/pdf/fs_blank.pdfhttp://thunderpanda.com/509/
Thunderpanda Troops:
http://thunderpanda.com/509/
Wednesday, May 13, 2009
News stories for teachers
There's a "Robot Hall of Fame" at the Carnegie Mellon Institute, and there's a list of new inductees. Some are fictional, some are real, all have had a very strong social impact:
http://www.robothalloffame.org/
An article on how people react to robots -- it's mainly in how you think of them:
http://www.newscientist.com/article/dn14666-robot-builders-seek-a-little-help-from-scifi.html
http://www.robothalloffame.org/
An article on how people react to robots -- it's mainly in how you think of them:
http://www.newscientist.com/article/dn14666-robot-builders-seek-a-little-help-from-scifi.html
Saturday, June 21, 2008
Science games: "Igor"
"Igor" is a "musical chairs" game variant that can be played with more than 6 kids and can be adapted to any of the sciences. Give the kids names related to the science activity that you're doing (hydrogen, carbon, oxygen as an example or maybe plankton, shrimp, fish, dolphins, whales ... anything at all, including the names of forces.)
If the group is large, make two people the same item (have 2 foxes, for instance, or 2 levers....) This kind of 'team' works particularly well for groups of 12 or larger.
Have the kids form a circle around you and pick someone to stand next to you. This person is "igor". Call out two 'team names' ("foxes and geese", for example). Everyone has to swap places and Igor has a chance to grab a seat. Last one to sit down becomes the new Igor.
If you get a situation where several people are standing around because they ALL want to be Igor, then make it 'first person to reach their seat is the new Igor.'
As a variant of this, you can allow Igors to call the items to be swapped.
An "all swap" can also be called, which causes a lot of very silly fun.
If the group is large, make two people the same item (have 2 foxes, for instance, or 2 levers....) This kind of 'team' works particularly well for groups of 12 or larger.
Have the kids form a circle around you and pick someone to stand next to you. This person is "igor". Call out two 'team names' ("foxes and geese", for example). Everyone has to swap places and Igor has a chance to grab a seat. Last one to sit down becomes the new Igor.
If you get a situation where several people are standing around because they ALL want to be Igor, then make it 'first person to reach their seat is the new Igor.'
As a variant of this, you can allow Igors to call the items to be swapped.
An "all swap" can also be called, which causes a lot of very silly fun.
Friday, May 09, 2008
Where to find robots
Some of you have expressed interest in buying your own kit to work with and play with.
This was the lowest price I found for the "Rock-it" Robot (be aware that kits come with solder and nonsolder options -- we use the non-solder options):
http://www.owirobots.com/cart/index.php?l=product_detail&p=6
Here's the Jungle Bot:
http://www.owirobots.com/cart/index.php?l=product_detail&p=14
Here's a cute and cheap little solar powered "king crab" robot:
http://www.owirobots.com/cart/index.php?l=product_detail&p=23
This was the lowest price I found for the "Rock-it" Robot (be aware that kits come with solder and nonsolder options -- we use the non-solder options):
http://www.owirobots.com/cart/index.php?l=product_detail&p=6
Here's the Jungle Bot:
http://www.owirobots.com/cart/index.php?l=product_detail&p=14
Here's a cute and cheap little solar powered "king crab" robot:
http://www.owirobots.com/cart/index.php?l=product_detail&p=23
Thursday, May 08, 2008
A short list of building tips and tricks
Get your own screwdriver kit. You should have a variety of sizes (most important are the Phillips screwdrivers -- the average cheap kit should do just fine.) The ones in the lesson kits aren't bad, but it's faster to work on kids' problems if you have your own set of screwdrivers.
Include a pair of needlenose pliers. They're good for getting out stripped screws -- and you can expect a lot of stripped screws in these classes.
A magnetic screwdriver is handy... BUT it also can put the motherboard at risk. The 1's and 0's in computer code are stored magnetically, and putting a magnet too near a chip will erase the programming on that chip. This is not a good idea when you're dealing with robots.
Use the magnets to find dropped screws on the floor.
Have kids put the parts they're not working on back in the bag and in their boxes and keep them there. Only have them do a few screws/nuts/bolts at a time to reduce the possibility of parts getting dropped on the floor.
(additional tips are welcome)
Include a pair of needlenose pliers. They're good for getting out stripped screws -- and you can expect a lot of stripped screws in these classes.
A magnetic screwdriver is handy... BUT it also can put the motherboard at risk. The 1's and 0's in computer code are stored magnetically, and putting a magnet too near a chip will erase the programming on that chip. This is not a good idea when you're dealing with robots.
Use the magnets to find dropped screws on the floor.
Have kids put the parts they're not working on back in the bag and in their boxes and keep them there. Only have them do a few screws/nuts/bolts at a time to reduce the possibility of parts getting dropped on the floor.
(additional tips are welcome)
Cool Robots
A small sampling of interesting robots:
Pleo is one of the newest robot toys on the market. This is an adorable little guy, about the size of a cat, with many play behaviors. He can learn certain things and in some respects acts as though he's alive. I have friends who own one, and I want one, too!
Pi-Tronics: this is a home builder's page and he has a number of easy robotics projects using cheap materials on his page.
Boston Dynamic's BigDog robot another one of my favorites. Built like an animal, it can carry packs, hop, jump, and walk around on very slippery ice without falling over. It models its motion from animal motion -- the video shows how it can recover its balance on a slippery surface. You almost forget that it's a machine that you are watching.
Leghorn is a "battle robot" from Japan. This small robot, which looks like a cartoon chicken, is one of the world's top "battlebots" in the lightweight division.
Honda's Asimo robot looks like a human and can speak and dance. I did see a performance piece where several Asimos danced a traditional Japanese dance in unison.
The Ever-1 Robot looks very human -- she blinks, moves her head, and gestures although if you look closely the movements are not completly convincing. She speaks and can understand around 400 words. One possible use for her is in information booths -- the Japanese don't like asking strangers for information and direction (I am glossing over some very complex cultural behaviors here... while the "don't like asking" is not precisely correct, it's close enough for a basic understanding.)
The Roomba vacuum cleaner -- this one is a great little robot that cleans up your house while you do other things. We have several -- a good investment for busy people. The I-Robot corporation also makes other interesting robots.
There's also a robot lawn mower. I don't have one, but I want one!
Lego Mindstorms is a wonderful robot building kit. I have several and they're fun to play with. The advantage of these is that you can build and rebuild robots into new configurations. Although the instruction set is fairly simple, people have built some odd and interesting projects with Lego Mindstorms.
The kits that we use in class come from the Omnico OWI robots. They make wonderful project kits for all levels of robot builders.
Pleo is one of the newest robot toys on the market. This is an adorable little guy, about the size of a cat, with many play behaviors. He can learn certain things and in some respects acts as though he's alive. I have friends who own one, and I want one, too!
Pi-Tronics: this is a home builder's page and he has a number of easy robotics projects using cheap materials on his page.
Boston Dynamic's BigDog robot another one of my favorites. Built like an animal, it can carry packs, hop, jump, and walk around on very slippery ice without falling over. It models its motion from animal motion -- the video shows how it can recover its balance on a slippery surface. You almost forget that it's a machine that you are watching.
Leghorn is a "battle robot" from Japan. This small robot, which looks like a cartoon chicken, is one of the world's top "battlebots" in the lightweight division.
Honda's Asimo robot looks like a human and can speak and dance. I did see a performance piece where several Asimos danced a traditional Japanese dance in unison.
The Ever-1 Robot looks very human -- she blinks, moves her head, and gestures although if you look closely the movements are not completly convincing. She speaks and can understand around 400 words. One possible use for her is in information booths -- the Japanese don't like asking strangers for information and direction (I am glossing over some very complex cultural behaviors here... while the "don't like asking" is not precisely correct, it's close enough for a basic understanding.)
The Roomba vacuum cleaner -- this one is a great little robot that cleans up your house while you do other things. We have several -- a good investment for busy people. The I-Robot corporation also makes other interesting robots.
There's also a robot lawn mower. I don't have one, but I want one!
Lego Mindstorms is a wonderful robot building kit. I have several and they're fun to play with. The advantage of these is that you can build and rebuild robots into new configurations. Although the instruction set is fairly simple, people have built some odd and interesting projects with Lego Mindstorms.
The kits that we use in class come from the Omnico OWI robots. They make wonderful project kits for all levels of robot builders.
Robots - Part two
In general, physical robots consist of 3 main parts: a programmable "brain", one or more moving parts, and one or more sensors. The "brain" may come pre-programmed so that the user is not able to change the behaviors of the robot. One of the most commonly used robot "brains" is the Basic Stamp http://en.wikipedia.org/wiki/BASIC_Stamp It's relatively easy to program this chip, and you can create a wide range of behaviors for it.
The company's home page has a lot of tempting robots and components http://www.parallax.com/
Choice of "brain" (and added memory) is the most important factor in determining what a robot can do and how easy it is to program. Needless to say, industrial robots do not use Basic Stamp chips as their "brains."
Choice of power supply also dictates how much a robot can do. It takes a lot of power to move a 150 pound humanoid machine -- only recently have robots like ASIMO been able to step away from the power cord for a few hours at a time.
A simple, programmable web emulation robot can be found here: http://home.att.net/~David.D.Barnett/tutorial.html You can program Karel to do a number of differet behaviors.
The company's home page has a lot of tempting robots and components http://www.parallax.com/
Choice of "brain" (and added memory) is the most important factor in determining what a robot can do and how easy it is to program. Needless to say, industrial robots do not use Basic Stamp chips as their "brains."
Choice of power supply also dictates how much a robot can do. It takes a lot of power to move a 150 pound humanoid machine -- only recently have robots like ASIMO been able to step away from the power cord for a few hours at a time.
A simple, programmable web emulation robot can be found here: http://home.att.net/~David.D.Barnett/tutorial.html You can program Karel to do a number of differet behaviors.
Robots - part one
Robot Basics
The most basic definition of robotics (that everyone agrees upon) is that it is a science that uses technology to design and make machines that do very specific tasks -- and which can also react to the environment in some way.
The line between what we call a robot varies from culture to culture (Japan's definition is a bit differen than ours) -- and the forms that the robots take are different from ours as well. Most robots today are used to make cars and appliances, or to work in some areas of nuclear plants and chemical plants where it woule be too dangerous for a human. The military and police also use robots to defuse bombs and to look into places where they think snipers might hide. Although robots in "Star Wars" and "Star Trek" do some very human things, our robots of today are a long way from being able to do those things. Most don't look very human -- and, in fact, many people would find a fully human-looking robot to be a creepy device.
There are internet robots that have no physical body, but are simply programs that do certain types of tasks. Usually they browse through the web looking for information and retrieving it for their owner. "Web spiders" (used by the search engine companies" are a type of web robot (called "bot" or "webbot") that search web pages, index them, and bring back the results to the search engine (like Google or Yahoo.) Other, more controversial ones, are software agents that do "bid sniping" on Ebay.
http://en.wikipedia.org/wiki/Internet_bot
It's useful to know about other types of robots, because classroom discussions may bring them up. For further reading on robot basics, see Wikipedia: http://en.wikipedia.org/wiki/Robot
Wikipedia is not entirely correct about the history of robotic things. The oldest story of something we might call a robot comes from ancient Sumeria (around 5,000 years ago or so); the story of a child of stone that grew so huge it threatened to shake the skies down.
The most basic definition of robotics (that everyone agrees upon) is that it is a science that uses technology to design and make machines that do very specific tasks -- and which can also react to the environment in some way.
The line between what we call a robot varies from culture to culture (Japan's definition is a bit differen than ours) -- and the forms that the robots take are different from ours as well. Most robots today are used to make cars and appliances, or to work in some areas of nuclear plants and chemical plants where it woule be too dangerous for a human. The military and police also use robots to defuse bombs and to look into places where they think snipers might hide. Although robots in "Star Wars" and "Star Trek" do some very human things, our robots of today are a long way from being able to do those things. Most don't look very human -- and, in fact, many people would find a fully human-looking robot to be a creepy device.
There are internet robots that have no physical body, but are simply programs that do certain types of tasks. Usually they browse through the web looking for information and retrieving it for their owner. "Web spiders" (used by the search engine companies" are a type of web robot (called "bot" or "webbot") that search web pages, index them, and bring back the results to the search engine (like Google or Yahoo.) Other, more controversial ones, are software agents that do "bid sniping" on Ebay.
http://en.wikipedia.org/wiki/Internet_bot
It's useful to know about other types of robots, because classroom discussions may bring them up. For further reading on robot basics, see Wikipedia: http://en.wikipedia.org/wiki/Robot
Wikipedia is not entirely correct about the history of robotic things. The oldest story of something we might call a robot comes from ancient Sumeria (around 5,000 years ago or so); the story of a child of stone that grew so huge it threatened to shake the skies down.
Wednesday, June 20, 2007
Absorption
This week I'm teaching a group of pre-schoolers a unit on absorption and water. It seems like a very simple idea (and the lesson plan is simple) -- we all know what absorption is. As I started outlining for myself the general information I wanted to give, I hit a real stumper:
"what's the mechanism for absorption and how do you explain it to a pack of 4 year olds?"
Uh.....
I knew what absorption IS, of course -- but how does it work? Internet turned out to be less help than I thought it would be. Dictionaries informed me that absorbency was "the property of being absorbant" (great. A circular definition. Everyone's favorite.) Absorbant was "the ability to absorb" (I was beginning to be suspicious at this point). "Absorb" means to "suck up" or "take up". I wasn't sucking up much knowledge from that.
The other dictionaries and encyclopedias were equally unhelpful. There's a boatload of tests for absorption, but no good explaination. After reading a number of articles, I eventually tracked down the answer -- an answer that's both interesting and surprising:
"what's the mechanism for absorption and how do you explain it to a pack of 4 year olds?"
Uh.....
I knew what absorption IS, of course -- but how does it work? Internet turned out to be less help than I thought it would be. Dictionaries informed me that absorbency was "the property of being absorbant" (great. A circular definition. Everyone's favorite.) Absorbant was "the ability to absorb" (I was beginning to be suspicious at this point). "Absorb" means to "suck up" or "take up". I wasn't sucking up much knowledge from that.
The other dictionaries and encyclopedias were equally unhelpful. There's a boatload of tests for absorption, but no good explaination. After reading a number of articles, I eventually tracked down the answer -- an answer that's both interesting and surprising:
The surprising answer is that water is sticky.
That's right -- it' s sticky. That answer seemed contrary to me until I explored it more thoroughly.
Stickiness is a physical property of things (ball bearings, for instance, are not sticky but the grease they're covered with is sticky. In the case of water, it's explained by a property called "cohesion" -- the electromagnetic forces that bond molecule to molecule. Because water molecules like to stick to each other (to "hold hands", as someone said) and water tends to "hang out" in globs and drops.
Think about it this way: sticky things stick to other things. If you put a metal spoon into a basket of beads, none of the beads stick to the spoon. Beads aren't sticky. If you put it into a cup of salt, salt won't stick to the metal because salt's not sticky. But if you put it into honey, when you pull it out there's honey on the spoon... honey's sticky. Oil sticks to the spoon.
So does water. We don't think of it as a sticky material because we use it to clean surfaces. But its stickiness... its tendency to "hold hands" with itself and with other substances gives water its most important properties: the ability to "wet" things and the ability to "soak into" things. It "slides into" small spaces and hangs around there (being very friendly), and adds to the weight of the object.
A good article on this is: http://www.exploratorium.edu/ronh/bubbles/sticky_water.html
Scholastic has a very nice little article for parents with some activities that will work for teachers or for curious adults who can't resist the chance to play with some sponges (that would be me!)
http://www.scholastic.com/earlylearner/age4/learning/sponges.htm
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