FLASHBACK: 'Billy Madison' Turns 20: Behind the Scenes With Adam Sandler in '94

O'Doyle rules!

It’s been 20 years since our favorite man-child passed the third grade the Billy Madison way, and ET was invited to the set with Adam Sandler back in 1994.

“It's not the most serious of sets,” Sandler told ET . “I thought it would be fun to get to do a movie, get to relive first through twelfth grade again, and try to do it the right way.”

WATCH: 'Scream 3' Turns 15! On Set With the Cast in 1999

It wasn't all glitz and glamour at the mansion, as Sandler had some misadventures behind the scenes -- like when he hurt his wrist playing tetherball with co-star Jared Cook.

“I was playing tetherball with that kid and he hurt me!” Sandler joked, “and he's over there bragging to his friends right now -- but he's going to pay for this.”

Man, I'm glad I called that guy!

Check out this video for more behind the scenes of Billy Madison.

Follow Ashley on Twitter: @AshCrossan