In dissection class, we dissected frogs, and learned quite a bit about them. In the class we had to measure our frogs. Most of the frogs in our class were 4 inches, except for two frogs that were both 5 inches.
Frogs have something called a nictitating membrane, which is a clear eyelid that lets them see under water. Believe it or not, humans used to have these too, but we lost them over time.
Frogs also have two sets of teeth, the vomarine teeth that are on the roof of their mouth and the maxillary teeth that are around the edge of the mouth.