I just did the science fair thing last week (2nd time).. K-5... YOU have a nice advantage of having time with a limited # of kids.... There is some stuff over in the journal section about it..
I was just showing them how to pan... No sluices or geology or history lessons.. I had to process 4-5 kids every 5 minutes. Some of them were dumber than a stump, some just didn't listen,
and lot of the little kids really needed a nap since it was an afterschool thing... Some did really well, some just didn't get it.....
Anyways... I'll tell you what I did/learned, having done this twice so far....
My little speech started off with 4-5 kids in front of me.. I asked them what they knew about gold. I had a poster behind me that said GOLD is HEAVY/dense... (I should have skipped the dense part).
"Its shiny.. Its expensive... blah blah"... Point to the poster... "Gold is.............."...... And the kids that were paying attention/awake "HEAVY!!!" ... Gold IS.... HEAVY!!!!
How heavy is gold? I made up some cups... Sand and rocks.. Black sand (and I explained that if they go out in their yard with a magnet, they can find black sand)... And a cup of carbide inserts..
Most, but not all carbide inserts are actually gold colored (handy) and they are primarily tungsten, which is within a few percentage points of the density of gold....
They all thought I was an idiot handing them a cup of dirt to feel... Just feel how heavy it is and pass it on.... The black sands... They started to pay attention, because it is heavier...
Then you bring out the cup of "gold"... And they all want to know if its real gold... I just told them if it was real gold, I wouldn't be here... That HEAVY cup of carbide inserts REALLY wakes them up.
This is where I wish I had a tube full of stuff to show them that the heavy stuff, when liquified(shaken) goes to the bottom... Next year maybe... Italian dressing is a half assed example..
Here are my cups... This year I made sure that black sand cup was full to the top, and the carbide also.. I left the sand where it is in the pic... Really want to let them FEEL the difference.
Then each kid got a cup and as I "tried" to show them.. We panned. This is where you will have a HUGE advantage over what I did... You'll have TIME... You can REALLY explain it, and you won't have
100 kids and 20 other booths in the gym making noise and distractions. Basically its shake and wash...
The problem is getting the right mix of dirt... You want the blondes to come off FAST, and you want SOME black sand to make the point and at least cover the gold. And then you want the black sand to
be of a size that it will easily wash off of the gold when the blondes are gone. I did .04 or so grams of 25 mesh, that's approximately 12-15 pieces per kid, less than $2 each. For black sand, I think I went
20-50 mesh, and I used a the socket head of a 5/16 SHCS for a measuring cup... NOT a lot of black sand, then 3 or so tablespoons of 20-50 sand and a bunch of rocks so they had to get their fingers dirty.
Here is a pic of what .04 grams of 25 mesh looks like, along with a cup of "pay dirt".
Then it went from the snuffer, down a small funnel into a vial. And they got to take it home. I had the parents there so I wasn't worried about a glass vial, you probably wouldn't want to go that route..
Some kids are going to get it in a second and make YOU feel like a second rate panner.. Some others are going to make you wonder how they have enough brain capacity to remember to breathe.
The first time I was drug into a classroom to do stuff, I was scared, I figured they wouldn't give a crap... I was wrong, really wrong... The hour set aside turned into over 2 hours, and they missed
recess and not a one of them said a word about it. And I had a lot of fun..
I'd try to keep it simple... What you think will take a half an hour, will take an hour and half... Little kids ask LOTS of questions... And its a lot of little kids... Like puppies. One puppy keeps you busy,
2 puppies keeps you 10X busier, 3 puppies keeps you 100x busier... Cool pictures, things to hand around(pan, snuffer bottle, big piece of "fools gold", etc..) , stories, history... And every one of
them is going to want to tell you a story about "This one time... "
You'll have fun.