Near the end of registration, each division will need enough players to field a team.  PYSA has recommendations and limits, and coaches also will have their own preferences based on how many kids miss games.

Since every player must play at least 50% of the time, teams may not have a roster more than 2x the game size.
||<tablewidth="200px">Division ||Game size ||HSC recommends ||PYSA recommends ||PYSA max ||
||K ||n/a ||no limit ||n/a ||n/a ||
||1st || 3v3 || 9|| 10|| 12 ||
||2nd || 4v4 || 11 || 12 || 16 ||
||3rd || 7v7 || 10 || 12 || 14 ||
||4th || 7v7 || 10 || 12 || 14 ||
||5th || 9v9 || 12 || 14 || 18 ||


PYSA numbers from the PYSA Registrar's manual, page 9:  http://www.portlandyouthsoccer.com/doclib/Registrar%20Manual%20rev3%20(2).pdf 

Check the registrar web page for updates: http://www.portlandyouthsoccer.com/home.php?layout=535216