We also tested their earphones and ear buds to see how loud they were.
The kids suggested some unique names for our model with the electronic
ear.
Over the two weeks of camp we tested 97 sets.
We had the kids set them at their normal listening level and then at
the maximum that their player could produce.
The highest normal listening level was 115 dBa and 25 of them were
above 90 dBa.
When the players were set to maximum the highest level was more than
115 dBa for 45 sets and it was more than 100 dBa for 63 sets.
Only 18 were less than 90 dBa.
After looking at how the ear works the kids understood that they could
damage the hair cells in the cochlea which would result in tinnitus and
hearing loss.
I hope they keep the volume down so that doesn't happen.
They put strips with a special pattern of bumps on them through the
bottom of plastic cups.
When they slid their thumb nail along the strip the cup said " Science
is fun."
The kids built kalimbas, an African musical instrument.
They used Popsicle sticks held by a strip of wood, some foam tape, a
piece of bamboo skewer, and two large binder clips clamping everything
together.
Then you slide the Popsicle sticks in or out to tune them so you can
play music.
Straw oboes, whizzers, and a video of the Tacoma Narrows bridge
collapse finished out the day.
Computers
The binary system is used
to represent numbers inside computers.
One and zero are all that is required.
The binary system uses place values like the decimal system except each
column increases by a factor of 2 rather than 10.
So pieces of wood with lengths of 1, 2, 4, 8, and 16 can be used to
make any length from 1 to 31.
The same idea lets these kids can display any number of dots from 1 to
31 by showing some of all of these 5 cards.
Here the dot cards have been replaced by 0s and 1s still representing
the columns of a binary number.
The number they are showing is 0x16+1x8+0x4+1x2+0x1 which is equal to
10 in the decimal system.
Each column of this clock display is a different binary number.
Taken together they represent 03:34:06.
Do you see how?
A binary checksum was the basis of a "magic memory" trick done with the
post-its on the board.
These kids are working on the design of a roller coaster.
When they were done the computer would tell them about potential
problems like too high a g load or too sharp a turn.
Chemistry
Safety first, they dyed their own pair of safety glasses that they will
use in classes during the week.
These bits of felt will be used to make moles which will serve as a
reminder of the mole that chemists use to calculate the quantity of
chemicals that are required for a reaction.
Mole construction.
And some completed moles.
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.
Generate some hydrogen by reacting aluminum with an acid.
Note that the reaction produces heat as well as enough gas to inflate a
balloon.
Secure it so that it can be ignited safely.
Completed
projects
Here the kids are showing off some of the projects they
made.
Contests
Every year campers participate in a variety of challenges.
The Straw Tower is one that they make at home and bring in to have
tested.
They put a container on top of the tower and then marbles are put in
the container.
There score is based on the product of the height and the number of
marbles it held before it collapsed.
Here is part of one of the tests.
Other contests were rocket golf, aluminum foil boat, periodic table
words, water balloon bomber, paper tower, hidden shapes, left turn
airplane, blindfold maze and Who Wants to Win $1,000,000 (not real
money).
When the campers had a little free time between the contests there were
puzzles and games to try.
Winners
Team and individual winners for the contests.
Field trip to Camden Park
This year's field trip
was to an amusement park where we
checked what we had learned in camp with real world observations.
We also had a lot of fun.
We all had a great time at camp.
Hope to see you again next year.