Passover starts today (in an few minutes or so). When I think of passover I think of matzah balls, and indeed there is a whole slew of matzo math (about halfway down that page) that was posted just a few days ago. But when I did a search on Passover, I also found a bunch of stuff about frogs, presumably because frogs were Plague #2 of the Ten Plagues. And when I thought of frogs, I thought of origami, which is automatically mathy because of all that geometry.
So here are directions on how to make a jumping origami frog!
Start with a square piece of paper, and fold/unfold along the two diagonals in order to make crease marks.
The paper I used was a darker green on the outside, and both of those two folds showed the outside (and hid the inside). Now fold/unfold in a horizontal line in the opposite direction (so the inside is showing:
Now that you have all your creases, you want to fold your paper into a triangle as follows:
Next you want to fold up the ends to make a diamond (well, a square) on the top. Here’s folding the right-hand first side:
And here’s after the left-hand side has also been folded:
Now continue to fold that top diamond. Fold the sides towards the center, as shown below:
Now you want to poke through the top two layers of the thing that was formerly a diamond, and fold it out. What’s a little confusing (to me) about this is that you’re folding an extra layer of paper that wasn’t touched in the previous fold.
Those legs are way too big — this guy needs to downsize! Fold the insides out (a valley fold I think it’s called, because the crease forms a valley when you look at it).
Now it’s time to add a fold so the boy can jump. First, turn him over. Then, fold up and back to make a crease. He reminds me a little too much of high school biology in the pictures below.
Now turn him BACK over and he’s done! To make him jump, put your finger on his lower back and press down. As your finger slides down, he’ll jump forward!
And now the frog can hop over and play with all his friends!!!
There are directions for frogs like this all over the web, complete with fold marks and everything. I used the ones at Wikihow as a guide to making mine.