Craig says he learned the facts of life at age seven while watching "Petyon Place." If Desi Arnaz Jr. and Craig are the same age (15 or 16), he would have to have turned 7 in 1960. "Peyton Place" didn't start airing until 1964.
Craig asks his mother for $100 for a surfboard which Lucy decides against as an unnecessary luxury. However, in "Lucy Visits Jack Benny", Craig packs his surfboard (much to Lucy's dismay) for his weekend in Palm Springs.