i saw one of the SAP 9's teams playing against a U/10 girls team last weekend, the 9's boys (granted it was one of the 'stronger' SAP clubs) were towelling the girls up pretty easily.
When we were leaving the one of the SAP 10's teams were warming up and the girls team they were about to play were waaaaaaaayyyyyyyy bigger than them. So not sure if those girls were 11's or 12's.