http://videos.howstuffworks.com/hsw/23879-frogs-the-development-of-tadpoles-video.htm?sort=most_watched&page=tadp&x=0&y=0

This video describes how a tadpole changes into a frog.

1. As the tadpole grows, it gets bigger in size.

2. Its hind legs will appear first, followed by its front legs.

3. Its tail becomes shorter and its lungs begin to form.

4. The tadpole has grown into a frog.