Campers sign in Monday morning.
 
And assemble to hear about the week's activities.

They were all anxious to begin.
     

Camp director Dr. Robert Arts

Monday campers learned safety rules that would apply in all their classes through the week.
They decorated a pair of safety glasses with their own choice of colors.
The glasses were for their use throughout the week and then they could take them home.
 

Some of our volunteers were  making tails for the moles the campers were  to put together.

Building moles.
These little stuffed ones were to remind the kids of the chemical mole.
If you need a reminder yourself it is the number of grams of a chemical that is equal to that chemical's atomic weight. 
That's 6x10²³ molecules.
They also checked what a mole of various other substances looked like.

And some after they are done.

Slime made from polyvinyl alcohol and borax solutions.
You can imagine polyvinyl alcohol (PVA) molecules as resembling limp strands of spaghetti that are as long as a football field.
When dissolved in water they easily slide over each other.
The sodium borate molecules are much smaller, imagine pinhead size.
Each solution is nearly as runny as water.
However, when they are mixed the borate ion forms links with random spots on the PVA molecules and the mix becomes very gooey.
The mix is still almost all water (96%) so it is surprising that it's consistency has changed so much. 

Campers learned about some of the the constellations of the northern hemisphere and built a star projector.

Cut out a lot of sky segments and carefully join them.
And punch a hole for each of the stars.

Hereare a batch that are half done.

Then they built and tested foam rockets.
It is a lot of fun.
And the practice will come in handy during the competitions on Thursday.

Here we are lighting a fluorescent bulb using static electricity.
Take an aluminum pie pan, tape it to a plastic straw, and hold it near a balloon that has been given a static charge by rubbing it on some fur (or beard).
Touch the pan while it is close to the balloon.
That gives a path to ground for the electrons that are being repelled from the balloon.
Take your hand away from the pan and no electrons can move to or from it because the straw is a good insulator.
Then touch the bulb to the pan and the bulb will blink as electrons from the person holding the bulb return to the pan.
The third picture shows a blink.

Ben Franklin would have recognized the electroscope I am holding even though we have used different materials for all of the parts.
Construction is simple, a container with a conductor through the top that has two pieces of foil leaves attached to it's bottom end.
When the electroscope is charged the two foils repel each other and separate.
Ben used a glass jar I used plastic. 
He used linen strings and later gold foil for the sensor, I used aluminum (a metal that wasn't known in his time).
He used a metal rod to hold the foils and I used a paper clip.
The kids made their own electroscopes with a plastic bottle, a piece of aluminized mylar folded to make two leaves, and a paper clip.
As a charged balloon or pie pan was brought close the mylar leaves would seperate.

We then turned plastic strips and campers into electroscopes using a Van de Graaff. 
It is misspelled on the board behind them.
When they were charged their hair was repelled and stood out in all directions.

They wanted to see what would happen to me too.

Then they got to see what electricity feels like.
They made a chain with fluorescent bulbs between the kids so thy could see them light up as the current passed through them.
The lights were dimmed for some of the pictures so the light from the bulbs would show up better.
We use a pan to make contact with the Van de Graff to make it easy for the first person in the line to control the size of the spark and the charge that they all feel.
You might say that they are "in charge".

A string of metalized beads on an insulating string is another way to get a charge from the Van de Graaff.
As they slide their hand along the beads the insulation provided by the string will eventually be insufficient to hold back the charge and a spark will jump between each of the beads and to their hand.
The anticipation can be as bad as the shock.

The apparatus on the left is called Franklin's bells. 
A charge on the bell closest to the Van de Graaff is charged because of a coronal discharge from the piece of foil attached to it.
The blue bob is attracted to it but as soon as it touches it has the same charge and is repelled.
Then it swings over and touches the other bell, is discharged and the process repeats.

We devoted one class to the study of sound.
We used a long spring as a model of how sound travels through the air as a compression wave and how it is represented on an oscilloscope (sorry no pictures).
The spring also is a good model of an echo as the wave bounces off its end.
Compression waves work in solids too.
This aluminum rod can have sound waves bouncing from one end to the other.

Anything that vibrates can produce sound waves though some may be too high or low for us to hear.
By making controlled vibrations in the range of human hearing we can make music.
Popsicle sticks are the source of vibrations in this kalimba all the kids made.
By adjusting the length of the sticks they can be tuned and they could play simple tunes.

Three of the sound sources the kids tried.
A completed and tuned kalimba.
The cup has a strip of plastic that will say "Science is fun" when you slide your fingernail along it.
The wood has a piece of fish line that can be played as a guitar or violin.
The vial from chemistry class holds 18 grams of water, one mole.

We also investigated resonance (periodic motion enhanced by addition of small amounts of energy in phase with the motion) at laboratory scales.
Then we took a look at one of the biggest engineering failures due to the resonance, the Tacoma Narrows Bridge.

We had the kids bring in their music players and earphones or ear buds.
They set them to their normal listening level and we measured the sound level.
Then we had them turn them up to maximum and measured the output again.
Most of this group had their players set at safe levels for normal listening but 6 of the 42 had theirs set at 90 dBa or higher .
In a work environment an employer would have to provide protection for that level of sound.
When set at maximum 3/4 of them put out unsafe levels with the highest being 123 dBa or higher.
That is above the threshold of pain and where very brief exposures can cause hearing damage.

We had the kids in each of the groups be as quiet as possible, whisper, talk normally, sing, and then cover their ears and yell.
Here are the results.
When you consider that the red and yellow groups had fewer kids by nearly a half they put in a good showing.

On Wednesday the kids made two kinds of accelerometers.
One measured horizontal and the other vertical acceleration.
They could use one to determine the forces in a car going around a curve and the other when they were on a trampoline.
They could also try them when we go on rides at the amusement park on Friday.

The kids had the problem of allocating a resource (trees) among several uses to allow them to support their group.

Here some of them have collected seeds, leaves and other materials to use in making sun prints.

Here are sun prints made using various grades of sun screen.
The sun print paper changes when exposed to ultraviolet light so the paper is a stand in for your skin.

On Wednesday the kids extracted DNA from their cheek cells and put it in tiny vials that they took home with them.

The computer class started with learning binary numbers and how computers use them.
Binary numbers are represented using only the digits "0" and "1".
By assigning different values for each column higher numbers can be represented.
Starting from the left the column values are 1, 2, 4, 8, 16, 32, ...
The number number the kids are holding in the last picture "01010" is no 16s, an 8, no 4s, a 2, and no 1s which make a total of 10 in our usual way of writing numbers.

Binary numbers are used to represent all sorts of data, from numbers, to music, photos, videos, and anything can be measured.
To limit errors a method of adding additional data to let you discover when a bit of data has been changed.
These Post-its represent 5 binary numbers and the added information needed to discover which one has changed.
Originally each of the rows and columns had an even number of each of the colors.
When one of the Post-its in the array is changed the number of each color in that row and column is now odd which allows you to recognize the one that has changed and then change it back.
Actual error correction schemes are more complicated but this illustrates how they work.

The kids used computer programs to design roller coasters.
The program then evaluated them to see if they would work, what the maximum G loads (accelerations) would be and would the passengers survive.
 
This picture from a past camp shows what two of this year's instructors looked like in 2001.
One of them is the daughter of the computer instructor.

I can't overlook this important part of the day.
The new cafeteria is open, bright and much bigger than the one we ate in previously.

Construction on the campus meant we had to detour through another building to get there.

During the week the campers were tantalized by the prizes that were to be awarded.
These are the first through fifth prizes for the straw tower competition.
And a few of the entries.
Some marvelous designs.

Testing how many marbles it could hold was nerve wracking for the kids.
The greatest height multiplied by the number of marbles it held was the score.

The Who Wants to Win $1,000,000 game presented the campers with science questions.
They would get harder with each round.

The foam rockets they built in Astronomy class were used in a game of rocket golf.

Design and build a paper bridge then test it to destruction to win points.
The more it held the higher your team's score.
There were lots of other contests too.

In the left turn airplane contest your score depended on how far down the hall it went after you threw it out a classroom door.



Use a rubber tubing catapult to fire four water balloons at a target. 
It takes three people to launch the balloon.
Only the last balloon counts for your score so use the first three to get range and bearing.

We had a few games and puzzles for the kids to play if they finished their contest round early. 
They tried to solve the eight queens, tangrams, and match stick puzzles.
This one is the game of Nim.

When the contests were over prizes were awarded.

The tower contest winners.

Campers and helpers are ready to load up for the trip.

On to the buses

At the park.
We got to study the physics of the rides and we all had fun.




We all had a great time this week. 
I hope that you enjoyed seeing a little of what we did at camp.
Check out some of the links below if you have time.