[Inspired by an email from Roy Henninger]

In USYS (CYSA in California) local league and tournament play, the age groups are based on a school year. Players born between August 1 and July 31 of the following year are grouped together, much as they are in school. In normal league and tournament play, players born between August 1 and December 31 play with and against players born between January 1 and July 31 of the following year. So, in league and tournament play, players with birthdays between August 1 and December 31 are at an advantage because they will generally be older, larger, stronger, and more experienced.

However, in ODP, players are grouped together by dates of birth within a calendar year - January 1 to December 31. In ODP, players born from August 1 to December 31 play against older players born from January 1 to July 31 of the same year. The August 1 to December 31 players are at a double disadvantage in ODP. Not only are the other players older, but these older players play a year up in league and tournament play and are used to a faster and more physical style of play.

As reported by one parent: "In my child's first ODP year, only three of thirty players that made the State ODP pool were born between August 1 and December 31. Two of these three players played up prior to the State ODP tryouts. For a player born between August 1 to December 31, playing up doesn't make you any older, but it gets you used to the faster pace and more physical play that you will experience at the ODP tryouts."