The next 3v3 ChallengeSports tournament is in Venice, Florida, June 14/15.

http://www.challengesports.com/VeniceSummer3v3/

U6/U7 Game Schedule for Venice Tournament

This is one of the last 3v3 tournaments close to South Florida before the National 3v3 Championships in Orlando on July 31 - Aug 3.  The Naples, Florida, 3v3 tournament will be the last one and it will be held on June28-29.