These 13 pictures show you why you shouldn’t make fun of your classmates!

Before they became stars in movies or music, celebrities who are world famous were ordinary kids who were nothing special...

These stars have undergone many changes as far as their hair, their bodies, their styles, etc. For example, Craig David and Dwayne Johnson have both lost a lot of weight. As for Kate Moss, she has totally changed. The same goes for Matthew Lewis, Eminem, Channing Tatum, and other stars you'll find in these pictures.

1. Channing Tatum

2. Eminem

3. Robert Downey Jr

4. Demi Moore

5. Julia Roberts

6. Dwayne Johnson

7. Craig David

8. Matthew Lewis

9. Ryan Reynolds

10. Catherine Zeta-Jones

11. Scarlett Johansson

12. Kate Moss

13. Joe Manganiello