Did you know there are hidden symbols, down the middle of your license plate (if you live in the US, anyway), that can only be seen from a 30 degree angle?
I didn't, but Vicki Cobb did, and she was good enough to share her secret, scientific knowledge with the rest of us in her book Don't Try This at Home! Science Fun for Kids on the Go. You can read all about it, and the science behind it, here, on her website.
It's pretty cool, because when you look at your license plate from any other angle, the symbols disappear, right before your eyes. Apparently, they are there to help the police identify counterfeit plates. And, they can be seen in the daylight, they just look even better, highlighted with a flashlight beam, after dark.
Not to mention, that a science lesson is always so much more exciting, when it takes place after bedtime.
As a side note about Don't Try This at Home! Science Fun for Kids on the Go, it is packed full of interesting experiments, investigating science in the world outside the house. However, paging through it, I found at least one experiment, I know won't work as written, and a couple of others that I'm doubtful about. We've found this before with her books, but I still recommend them, because with some research, and a bit of tweaking, they are great experiments, and a lot of fun. Just try them out ahead of time, before you attempt to wow the kids.
It's great to be a homeschooler.