The system used by most federations (including US Soccer since 2016) where age groups are determined by the calendar year (Jan 1 - Dec 31) rather than the school year.

A rule in some youth leagues that ends the game early or allows the losing team to add an extra player if the score difference becomes too large.

A laminated card or digital profile with the player's photo and birth date, required by referees to verify eligibility before a match.