Here is another one for you know-it-all straight from the US Lacrosse website - link AND text just to make sure you get it:
(http://www.uslacrosse.org/TopNav2Right/Events/2013NortheastChampionships/RulesPlayerEligibility.aspx)

Events | 2013 Northeast Championships | Rules & Player Eligibility


Rules
Game rules will be posted as the event draws near.

Player Ages and Eligibility
All current US Lacrosse members who meet the age requirements below are eligible and welcome to compete in the 2013 US Lacrosse Northeast Championships.

Birthdate Status
Born on or after 9/1/2001 - Eligible for U11 Championship
Born on or after 9/1/1999 - Eligible for U13 Championship
Born on or after 9/1/1997 - Eligible for U15 Championship

In the U15 division, high school players meeting the age requirements are eligible to play, provided that the player’s high school season has finished by the June 21 start date of the US Lacrosse Northeast Championships. If a player’s high school team remains in competition at the time of the US Lacrosse event, that player is not eligible, in accordance with "US Lacrosse Youth Rules and Best Practices."

Proof of Age Submission
All players who wish to participate in the US Lacrosse Championships in the U11, U13, and U15 divisions are required to submit to US Lacrosse a copy of a proof of age document in order to be eligible to participate.

Acceptable proof of age documents:
• Birth Certificate
• Passport
• School ID (if date of birth is present on ID)
Proof of age documents should be faxed (410-889-0744) or e-mailed to Shannon Minter after the parent/legal guardian completes a player medical waiver.

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