With nothing more than a piece of paper, you can construct a frog.
Throughout these instructions, the dotted lines are where you will fold on the next step. Click on any picture to enlarge it.
Step 1

Start with a sheet of paper. You can use ordinary computer paper, colored paper, or origami paper.
Step 2

Fold one corner diagonally down to the opposite edge, so it will make an X shape out of the creases when you unfold x|right]] Open it back up and fold the paper on the other diagonal.
Step 3

Trim any extra paper outside of the square you just made, as shown. Skip this step if you are already using square (origami) paper. True origami only uses folding to create shapes--that means no cutting or tearing.
Step 4
Open the square back up and fold it backwards, across the intersection of the two diagonal lines.
Step 5

Open the paper again and push in the sides.
Step 6

Form a triangle.
Step 7

Fold the outside corner up to the top point.
Step 8

Fold the other corner up.
Step 9

Fold the new corner in, towards the center line.
Step 10

Fold the other corner in towards the center.
Step 11

Now fold the top corners back out, until the edge is even with the edge underneath.
Step 12

Repeat folding the top corners, as shown above, except on the other side.
Step 13

Turn the paper over.
Step 14
Fold the outer corners towards you, into the center.
Step 15

Fold the outer corners back out, so that they're even with the outside edges. You're almost done.
Step 16

Fold the frog in half.
Step 17

Turn the frog over so the legs are facing away from you. Now fold those in half so it looks like the picture.
Step 18
Ribbit!
Tips
- Crease your corners well. Your frog will "jump" better.
- Thin paper will work better. Thick paper like construction paper is hard to fold and the frog will jump poorly.
- Try it with lined paper the 1st time then use different paper to copy what you've done!
- The smaller the frog, the farther it jumps.
Warnings
- Scissors can be dangerous. Get the help of an adult if you are a child under 7.
- Beware of paper cuts!