undefined | A North Carolina teacher has become internet-famous for teaching kids about the wonders of science and the wonders of washing their hands at the same time. Donna Gill Allen, of Gray’s Creek, made a Facebook post about a science experiment that’s since gone viral.
“To all my teacher friends this is the grossest yet coolest experiment,” she wrote, in the caption of her Facebook post. “I did this while teaching about germs and how they spread. You use three pieces of bread. You let all the kids see you put a piece of bread in a baggy with a glove on (hence ‘controlled’) then you wash your hands and put a piece of bread in a baggy for ‘clean.'”
“Last but definitely not least,” she concluded, “You pass a piece of bread around and let every kid in class touch it.” In the weeks after the project, the students can watch the mould developing on the “germ” bread. Allen’s project is a neat way to teach kids about the importance of hand-washing. But what other science experiments have been circulating the web recently?
1. Walking on Eggshells: If you leave eggs in their carton and have a person help you to leverage yourself up on top of it, you can literally walk on eggshells.
Lesson Learned: The arch shape of the egg is actually pretty strong when force is evenly distributed evenly on them; it’s only when the pressure is uneven (as in when you crack an egg on a bowl) that it’s fragile.
2. Magic Bag: Fill a zip bag halfway up with water, seal it, and poke pencils through from one side to another. You don’t need to do it over the sink; the bag won’t leak at all! Keep adding pencils until you’re bored.
Lesson Learned: plastic bags are made of long, thin chains of molecules called polymers, and they give the plastic its “stretchiness.”
3. Making an Electromagnet: if you have a battery, thin copper wire, and an iron nail, wrap the wire around the nail, leaving about 8 inches of the wire extending from each end. Attach one of the wire ends to the positive side of the battery and the other to the negative size. If you bring the point of the nail near paperclips, it should pick them up.
Lesson Learned: The magnet will work when the wires are attached to either side of the battery but will stop working when the wires are taken off. This is a good introduction to electromagnets – magnets that can be turned on and off.
4. The Straw Is Mightier: All you need is a potato and two straws. Take the first straw and try stabbing it into the potato. Then, try it again with the second straw, but place your thumb over the top hole of the straw. This time, the straw should go further in!
Lesson Learned: When you put your thumb over the top of the straw, it keeps the air in, forcing the straw further into the potato because of the air trapped in it. Air pressure is a powerful force!
Steve Spangler Science
