MISSION BAY — Mission Bay Little League has opened its registration process for the spring 2011 season. Parents will save $20 by signing up their children prior to Jan. 1. Tryouts will be held on Jan. 22 and Jan. 29 for ages 7 to 12, and the league is open to all children ages 5 to 18 that live in the 92109 or 92307 ZIP codes.