Carol is upset about Greg making the football team, fearing he'll get hurt.Â She even says no son of hers is going to play that game.Â However, Peter was on a football team in the season 2 episode, "The Drummer Boy".
The origin of Alice's cake recipe she writes on the blackboard - which accidentally gets erased - seems to change! When she was trying to figure the ingredients out with the girls she said it was "the best cake I ever created". But when Peter erased it she commented about it being a "recipe that's been handed down from generation to generation...ending with this one!"
(Greg comes homes with a bruise on his arm)
Carol: Oh, Greg!
Greg: Mom, it's just a bruise.
Carol: That is the biggest bruise I have ever seen in my entire life! See, this is exactly why I was so worried about you playing football!
Greg: Mom, that's not from practice. I bumped my arm in math class.
(cue laugh track)
Carol: Oh, well...
Greg: I'd be happy to quit math if you think it's too dangerous.
(Greg and the coach in the locker room)
Greg: Coach, the ribs are nothing, it's telling my mother that's gonna be painful!
If you would take notice at the guy that's playing Greg's coach, he also played the coach for Peter's football team in season 2's The Drummer Boy.
Ironically, Greg would rejoin the football team the next season and wound up leading Westdale High to the City Championship in the episode "Quarterback Sneak" in the final season.
This stock footage of the football game was the same big game that Westdale beat Fairview at in "Quarterback Sneak"