We have an adult-junior league that bowls every Sunday at 5. Because of the 2-bowler format (one adult/one junior), the league finishes in less than 90 minutes each week, which doesn't leave much time for socializing or getting to know the other teams.
In order to build a community, we've done several things.
First, every week, after practice, before league starts, we have a mini "contest." We alternate weeks between the adult and the junior bowler (although in any league you could do the same by calling out the bowler's position on the team), and we ask the bowler to get on the approach and
A) get a strike, or B) get a split, or C) get the lowest count possible. The house gives away free games to the winner, but it keeps everyone active (and doesn't favor just the higher bowlers).
I've seen some centers do something similar by having each team pick a bowler to throw a strike, and they keep having the bowlers throw strikes til there is only one bowler standing, and that team gets a free round of sodas. It doesn't cost the house much, and it definitely builds league loyalty.
Also we save all our awards til the end of the year, and we have a pizza party on the sweeper night. We either turn up the music, or turn on the black lights (we let the kids vote), and everyone bowls no-tap. The center throws in a few small prizes for the kids (leftover promotions--backpacks, ball
bags, fanny packs, a few free games). After bowling, we present all the awards earned all season. Even for 20 teams, the pizza party doesn't take much out of the prize fund, and everyone has a great time.
