International level 5 teams are 14 years and older, and International level 6 teams are 17 years and older. I'm pretty sure they're different from level 5 because tumbling isn't worth as much on the Worlds scoresheet. It's only worth 10% of your score, building skills (stunts, pyramids, etc.) are worth 65%, and choreography is worth 25%. Whereas on regular level 5 Worlds scoresheets (Small & Large All Girl, Unlimited, Semi-Limited, Large & Small Limited Coed) tumbling is worth 35% of your score, building skills are worth 45%, and choreography is worth 20%.