Danica McKellar
Danica McKellar was well-known for her roles in the 1980s. She appeared in TV shows like The Twilight Zone and The Wonder Years. In recent years, she has lent her voice to characters in shows like Phineas and Ferb and Transformers: Rescue Bots.
What's even more surprising is that she worked hard to earn a Ph.D. in math! If you want to learn math from her, she has written books like Girls Get Curves: Geometry Takes Shape and Kiss My Math: Showing Pre-Algebra Who's Boss.