Youth hockey has really worked it out. Within each age division, Jan 1 cutoff, there are:

House - new player, and players who might no be good but love the game
B Team - Travel lowest level
Lower A - Travel next level
A - Travel with mostly or all minor age of the division
Upper A - Travel with a mix of minor and major ages of the division
AA - Travel with a majority or all of majors of the age division
AAA - Tier 1 hockey ( lots of plane rides)

Bottom line is it is all age based and strictly enforced, especially by the tournaments who will reclass teams to other tourney divisions based on records and mix of ages on the team.