Deprecated function: Array and string offset access syntax with curly braces is deprecated in include_once() (line 20 of /home/raw3y9x1y6am/public_html/includes/file.phar.inc).
I took this photo while working on the "Micro-Crystals" video, and thought this might be a challenge. What common chemical is this? Hint: The colors are from polarizing filters. The crystals are normally clear.
This activity is a result of preparing for another experiment. It began as an experiment with insects, but it was getting too long, so I chopped it in half. (The experiment, not the insect.) This time we will look at the amazing variety of insects that can be found almost everywhere, and in interesting way to collect them.
This activity is one that I use for Schoolyard Ecology workshops. It is a great warm up for getting people to slow down and really look at the world around them. Once they do, they are amazed at all of the things they have been missing, and they never look at a lawn in the same way again.
This experiment is a chance for you to do some scientific research on a problem that has never been solved. We all yawn, and you have probably noticed that if someone else yawns, you do too. Why? There are several hypotheses, but none has enough solid evidence to become an accepted theory.
In the Sorting Salt and Pepper video we saw that we could mix salt and pepper into a pile and then separate them easily by using the static charge on a balloon. That is one way to separate salt and pepper, but there are many others. How many can you think of? Don't read any more until you have spent some time thinking of as many different ways as you can.
In part one, I left you with a challenge. We put a little sand into a glass of water and stirred it. Instead of moving to the outside edge, as we might expect, the sand gathered in the center of the glass. I left you with the challenge of telling me why.
Congratulations! Several of you got the right answer, and several more got it at least partially right.
