Playing with boys at checking depends on the girl. Is she strong on her skates? Is she physical? Does she have some size to her? Does she keep her head up when carrying the puck? The lower the level the rougher checking is. Depending on your location the best girls program is Jr. Flyers. Little Flyers & Princeton Tiger Lillies are ok. Up north, Colonials are good. Liberties out of Voorhees are getting better, but not at the AAA/AA level of JF, LF, PTL or Colonials. If she can hack it stay with the boys for a year.