Seriously, there was every conceivable kind of recreation either free or very cheap — movies (25¢), game rooms, music rooms (where you could check out any musical instrument and practice on it), libraries, athletic fields, judo classes, bowling alleys, a baseball team (the Vikings), the Teen Club, the Snack Bar, the Field House in HiCoG (three places within a few blocks to get hamburgers made to order for about a quarter). You could ride on the Paternosters in the IG Farben building... No end of fun. And to top it off, we were in Germany! So there was even more fun to be had off base, and in those days you could ride all over the city, all the way to the Taunus mountains, for pocket change on the trolley, go swimming in... Where was it? Bad Vilbel? No, Oberursel! (Thank goodness for Google.)
And there was the experience of being thrown together at close quarters with all kinds of people of every race and religion and background from all over the USA and elsewhere; this was when schools were still segregated back home. Friendships were forged in Frankfurt and other bases like it that would have been unthinkable back in "the world".
The one annoying part was the rank-based class system imposed on (and accepted) by our parents. Officers and EMs and their families mostly did not associate. There was the Officers Club and the EM Club and they were two separate worlds (and the NCO Club so that makes three), but then there was the world of us kids — school, the Teen club, the hangouts, the playgrounds — that knew no rank or class boundaries, and that was where a lot of us learned to thumb our noses at authority... A habit I never quite broke.