How many movies were in the series revenge of nerds?

There are 4 movies in the Revenge of the Nerds franchise:

1. Revenge of the Nerds (1984)

2. Revenge of the Nerds II: Nerds in Paradise (1987)

3. Revenge of the Nerds III: The Next Generation (1992)

4. Revenge of the Nerds IV: Nerds in Love (2007)