Science Toy Maker

This guy is a middle school teacher.  His site has about 40 carefully-selected science toys that can be easily made for cheap or even free.  Each one has instructions, images, and most have videos and animations.   Everything is explained which makes YOU look like the expert!

http://www.sciencetoymaker.org/

Class-opener demos for any age (almost) from the Exploratorium

The Exploratorium in San Francisco is literally the mother of the modern hands-on inquiry musems (we have five of them here in Oklahoma!).

They have oodles of resources for science teachers and here is one:  Over 100 quick demonstrations and activities.   Some require advance  preparation and some do not. They call them “Snacks”.

http://www.exploratorium.edu/snacks/

Franklin’s Bells

Use static electricity to get a couple of aluminum pop cans ringing.   It gets its high-voltage from a sheet of aluminum foil taped in front of a TV set.

OK folks, this one is scary, but that’s part of the thrill.  The voltage is high but the current is so low it probably won’t hurt you, much like a really good spark from walking on a carpet.    It might also ruin the TV.  I know, I’ve done that before.   But hey, what else can you do with an old CRT television?  It won’t bring $5 at the garage sale.

You will need to set up two cans, one wired to ground and one wired to a sheet of aluminum foil which is taped over the TV screen.  An LCD TV will not work; it does not produce the high voltage needed.

Like most of these, getting it adjusted so it works right is the tricky part.  Once it works the pendulum will oscillate back and forth REALLY FAST and ring the bells.   The process of getting it adjusted will quite possibly cause a few harmless sparks to your own self, much to the great glee of the children nearby.   A little showmanship here can’t hurt.

Benjamin Franklin actually made a similar device that he used to let him know that there was enough lightning outside to begin his experiments.  He got very lucky though with his experiments.   When other scientists tried to duplicate his work a number of them got electrocuted by the lightning.   Your version will be much safer.

Look at the pictures.  Search the internet for images, videos and instructions for “Franklin’s Bell”  or “Franklin Bells”.   Look at this example of instructions, then build your own.   http://sci-toys.com/scitoys/scitoys/electro/electro4.html    And yes, there even is a version using electric flyswatters for the voltage source.

My favorite image of this is at http://vimeo.com/51183310

Fun with electric motors – 2

Here is an even easier, quicker motor to build.  It is more for older kids though, and safety goggles are absolutely necessary!   This little sucker takes less than a minute to assemble and gets up to thousands of RPM’s in a hurry.  If it comes apart (and it easily can) at that speed it might send that woodscrew flying, hence the goggles.

The critical part is the little neodymium magnet.

You usually have to give it a spin to get it started.

Look at this link for instructions, then search the internet for some more pictures, videos, or  instructions.   http://www.evilmadscientist.com/2006/how-to-make-the-simplest-electric-motor/    Search for “world’s simplest electric motor”

 

They are so easy to build, you can almost do it from the picture alone.

 

Fun with electric motors – 1

There are lots of ways you can make a simple electric motor.   Lots of them do not work.   The best one I have found is called “Beakman Motor”, name after the character on Bill Nye.   One good example of how to build it is at http://sci-toys.com/scitoys/scitoys/electro/electro.html#motor

Search the internet for images and plans for the Beakman Motor and that will help you design your own.  Keep a couple of tricks in mind:

a) Use a regular battery holder, like you can buy at Radio Shack.  Using a board with nails (see the picture) often leads to failure and nothing dampens a science activity with kids like one that does not work.

b) Pay real attention to stripping the wire.  Wire is coated with either enamel or plastic, and it won’t conduct electricity until the coating is removed.  In many of these Beakmans, the end of the coil (called the “armature) have the coating removed on one side but not the other.  That is critical to making it work.

c) Use a larger battery.  Whether you pick a D, C, or even AAA they all have the same voltage; about 1.5 volts.   What you need is more current, which is not the same.   The D and C cells provide more current.  Be aware, these little motors do eat through batteries in a hurry.   Have fun!