While on a giant pool table, Robin points to the oversized billiard balls and says to Batman, "Look at the size of those balls." This joke will likely go over younger viewers heads, as they are giant billiard balls.

Aunt Harriet, as in the previous movie, hints at a homosexual relationship between Bruce and Dick, mentioning that they "sure do go on a lot of fishing trips."

At the end of the movie, Robin exclaims "Holy Hugh Hefner," who is the creator of Playboy magazine, which is an adult magazine featuring nude or scantily-clad women.

During the end credits, all of the movie characters are seen dancing. Catwoman is seen shaking her butt, while wearing skin tight clothes.

Just punching, kicking, etc, much like the 60's Batman show, which is also blurred out by the iconic sound effects of the show.

In the scene where Robin is transformed into a two-faced being like Two-Face, he is implied to flip off Batman. The gesture isn't actually seen, but the implications are hard to miss.

None, but there are puns made involving the lines "make an asp of yourself" and "look at the size of those (billiard) balls," and an implied use of the middle finger respectively, as mentioned above.

Two-Face's plan of turning everyone in Gotham into two-faced beings like he is can be a little unsettling to younger viewers.