"I was more nervous at the spelling bee than I am now, I don't know what that says," Ben, who has three kids with Jen Garner -- Violet, 7, and Seraphina, 4, and Samuel, 11 months -- told Ryan Seacrest on the red carpet.
"There were a lot of words. Let me tell you something, you and I might have been in trouble."
Jen said Sunday meant "mayhem" for the Affleck household.
"Our daughter was in a spelling bee at the local rec center," Garner told the E! network. "I was in hair and make-up so I couldn't take her, so Ben took her in the middle of everything. She won!
As RadarOnline.com previously reported, despite being snubbed for a Best Director nomination, Ben cashed in at the Oscars with Best Picture, Best Adapted Screenplay (Chris Terrio) and Film Editing (William Goldenberg).