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How can I get 13-16 year old school students to get interested in Science and Math. I only have 8 hours per semester.I am doing this for my Alma Mater...the size is 100 students.


ANSWER: Well, you have limited time, so a large group project is probably out of the question unless you can assign them to do work at home.  The best way is perhaps a science show.  I did a lengthy science show for kids.  It doesn't always take much money.  

It would help me more if I knew how your time was distributed and what resources you have.  Do you need to keep this computer-based, or can you buy some cheap props to show kids science projects that they can do at home?  If they see cool science and they can do it at home, some of them will do so.  Do you have it just a few hours per week, or is it all in one 8-hour shot?  These details guide what kind of approach you take to make a simple, cost-effective plan to get them interested in science.  It's also possible to send some of them to places like to try to do science fair projects.  Eight hours per semester by itself won't do much unless you can get them to take that interest in science/math home with them.  That's far more important to meaningful interest in these subjects.

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The 8 hours are spread over 8 x i hour sessions. We have funds for some props and we have access to computers...but its is not a computer based program.

We would like to do demos and experiments but would also like them to do some of their own experimentation. Can you elaborate more on the allexperts approach. I intend to break the group into classes of about that advisable?

Thank You.

ANSWER: So to set the scene and then to the plan later...  In my experience, there are a few things that play well to getting students really interested in science: demonstrations, jokes, music, references to things they know...and most importantly you have to appeal to their dreams.  My favorite and most successful of all is that I take a lot of hand surveys and I ask them some yes/no questions.  The last question is always "who doesn't like being told what to do?"  That gets all the hands.  I explain that even if they're the boss of a business, they still take orders from customers.  Lawyers do what their client wants.  Doctors respect patient wishes.  But artists and scientists get to come up with their own ideas of what to do...and science pays far better.  That's a hook, and it's one you need to work in often.  On to the plan:

OK, you'll have to decide on exactly how to play off the mix of project and demonstration.  I would start by watching a bunch of science youtube videos at home to see if you can't get inspiration.  Search words like "science demonstrations you can do at home" work well.  And words like "ferrofluid" and "liquid nitrogen demonstrations" work well.  From there you need some demos, some challenges to take home, and perhaps some projects.  The way it is split up, I recommend that you tell the students to start thinking of science projects to do, or something short like a science demo challenge.  If the whole class wants to do something huge (a class approached me once wanting to construct a balloon that would lift each student, and do it in the gym) then they could do one project and get expert advice, or a project per class.  I recommend that you keep it to the science demonstration level, most students try to bite off more than they can finish, like launching space-going rockets, for full science fair projects.  Set a schedule for them to accomplish turning in some photos or a paragraph on their progress.  You have to hold them to this, but make it easy to do (like a few cell phone pics of the progress that week).  Keep focus on the science, if you need a day when you're out of demonstrations that week, definitely just take some time to compile a list of coolest youtube videos of science demonstrations. You can make a "funniest home videos" contest out of it and have students submit their favorites in a contest...and also vote on the winning science video under a certain number of minutes.  Contests keep them engaged, science may take a back seat to the cool factor.  Also don't be afraid to use a little music:

If you want to start with a science show, here's what I had for mine:

1 Van de Graaf generator
2 hand-held Tesla coil
3 Light bulbs (flourescent, and some specific gases like neon that you could get from a sign)
4 dry ice
5 soap, food coloring, water
6 balloons
7 A very large glass and large candle that just fit inside it with a small gap about halfway up if I put the glass over the candle
8 An air pump (vacuum cleaner like a shop vac works fine, or hair dryer)
9 A turntable with a bicycle wheel
10 small quantity of ferrofluid (surprisingly cheap online) jar/50-50 rubbing alcohol/strong magnet
11 sometimes liquid nitrogen

Key experiments, by item:

1 If you ask who wants to get an electric shock by the end of your presentation, all hands will go in the air.  Let them line up and get a zap on the back of the hand from the Van de Graaf.  You can also get kids to stand on a book up on some styrofoam and see whose hair goes up the best if they hold on to it while it charges up, but keep a grounding rod nearby.  You can milk a Van de Graaf forever with different demos discharging through fluorescent light bulbs and gas discharge tubes.  You really need to let the students get their hands on it, so it takes a while. this is a good place to start for demos.  If yours comes with accessories, use them (like the twirly thing with sharp points).  Also fully explain the science behind the Van de Graaf and don't be afraid to dismantle its top to show them how it works.

2 The Tesla coil is a high-frequency transformer, it makes lightning bolts and will be far more impressive on your light bulbs.  It will also zap water and chains of light bulbs.  If you wrap a fluorescent bulb halfway in aluminum foil (and ground it), you'll be able to show how that can cut off the flow of electricity, even outside the bulb.

3 These go with 1 and 2.

4 This is where it gets really interesting and do-at-home stuff follows, but I'm going to post this now and go into more detail tomorrow with an edit.  It's very late in my time zone.  Remind me with a follow-up question if I forget to get back to this in about a day.  I'll keep running through demos and then suggest some cool projects for the students...I'd use the "save answer temporarily" option, but I wanted to get you started.

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QUESTION: Very useful suggestions...thanks you Sir. :))

I'm not done yet!  Just delayed, overseas.

4)  The first thing I do with dry ice is totally good for a class.  I always used a cannonball to break up my dry ice, for dramatic effect.  Take a chunk of dry ice and put it in a glass of water.  Of course, it makes fog.  Now ask the students what will happen if you put some food coloring in the water.  Being heavier molecules than water it doesn't make a strong vapor, of course the fog doesn't actually change color, but most students think it will.  A show of hands will tell you that.  It leads to a discussion of condensing water vapor making the fog itself.  If you get enough plastic cups and some sweetener, you can give a cup of fog-making water to each student (small chunk of dry ice per cup) and eventually you'll end up with sodas for everyone.  Dry ice is usually sold in blocks of a few kg, so you should have plenty.

4a) The next dry ice experiment is to put it in a bowl or tupperware container with a smooth lip and some water.  It makes fog, of course, but if you take a soapy rag (videos are on youtube ) and stretch it over the edge you make a bubble.  That bubble will expand to very large size.

4b)  If you put dry ice in a fish tank with a little water, it will start to fill with fog.  If you want to display the difference in density with air, you can blow bubbles and they should float at the boundary.  If you want it to be more mysterious, use no water and just wait a bit with the fishtank covered.  When you uncover it and blow bubbles into it, they should float on a more invisible layer.  If you have access to very dense sulfur hexafluoride, you can use that instead and substitute balloons. You can also use it like a helium balloon to make a super-deep voice (yes, you can inhale it).  

4c)  If you have permission, you can blow up a small plastic bottle filled with small chunks of dry ice and water.  Ask the students which will make the biggest bang, more water, more dry ice, or more empty space to pressurize?  If you do it show-of-hands style, one question at a time, pause before that last one.  Then they'll understand.  IF YOU DO THIS you need a blast shield.  A cardboard box is the easiest and in some ways best.  Practice first.  You fill the bottle about a quarter way with small chunks of dry ice (you can juggle the pieces, just don't hold on to them). Fill in with some water, cap it, put it down on the floor and under the cardboard box (which may or may not blow apart, but will shield the students from any flying pieces) and then run away in hilarious fashion.  The suspense is huge, but they'll be really quiet to hear the creaking of the plastic as it stretches to breaking.  

5) This went with 4 a-c.

6)  If you have a balloon and an air pump, you can do one of the coolest demonstration. The air pump can be anything from a hair dryer to a shop vac to an air track air pump.  Even a small leaf blower, if the space is big enough.  If you put a little water (teaspoon? depends on the air source) of water in the balloon and place it in the air stream (pointing up), the balloon will stay suspended even if you lean over the air stream.   You can lean it over students heads and bonk them on the heads.  You can use a bit of sand or whatever instead of water.  It's an open question, what best stabilizes the balloon?  The hope is that they'll take the experiment home and do it there (not the exploding one).  

7)  This is a classic trick that some students will have seen, but you can amp it up to be good for a large room if you have the right candle and glass vessel.  You put a candle in a big dish of water and light it, then you put some food coloring in the water.  Place the glass vessel over the top of the candle and leave it there until it uses all the oxygen.  There are a lot of bad explanations on the internet about this.  At first, O2 and carbon will make CO2, so that's a 1-for-1 molecule conversion, but the hydrogen in hydrocarbons will go H2+2O2 -> 2 H2O and cause a pressure increase.  That, with the temperature, will bubble out some air from the water.  Then the oxygen will be exhausted and two things will happen.  First, the temperature will drop and the pressure will drop.  Also (MORE IMPORTANT), the water vapor will condense and the system will pull a serious vacuum.  The water will pull in around the sides of the candle, and with a pale candle and food coloring, everything will see it drawn up into the glass.

8)  Oh, see 6.

9)  This is a classic.  Ask what makes the Earth go around.  It's actually the wrong question, but field a few answers.  It's the wrong question, because the Earth orbits in outer space...the right question is "what is there to stop the Earth from spinning?"  Nothing, so it keeps spinning.  Then you can rotate the wheel pointing down (it needs a handle), step on the platform, and then reverse its direction above your head.  Conservation of angular momentum will make you spin in the direction the wheel initially spun.  Get other teachers to do it, or other kids.  It leads to discussions involving rotation.

10)   I made a very large version of this: way back, and it seems to have become very popular.  I tricked little kids into thinking it was a monster named Fritz who liked magnets, then explained it.  Since I had a whole liter of it from like or somewhere, I made tons of little versions of this demonstration with little strong magnets and gave them to the middle school teachers when I brought the show to them.

11)  Liquid nitrogen is awesome, if you can get it.  There are a zillion demonstrations you can do involving balloons and ping pong balls.  You can also dunk your hand in it.  If you're interested in more of those, post a follow-up.  

12)  I know, I only listed 11 things...but if you have a small glass, a large glass, and you can put the small one inside the large one then you have another demo.  Pour vegetable oil into the small one in the center.  Everyone will see it.  Then keep pouring until it spills over and fills the larger glass.  Because of the matching indices of refraction (water and oil are about the same), the small glass will disappear.

13)  If you have advanced students, a glass (beaker?) of water and a scale, you can dunk something in the water to show the buoyant force.  It will weigh more just from dangle an object on a string inside, because the force is also exerted downwards on the water (Newton's laws).  Then if you let the object actually hit the bottom it will weigh still more.  Fascinating demo for more advanced students.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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