I'm a 17 year old High School Junior and was approved last week with no problems.
I just sent evidence proving i am enrolled in school right now.
I sent my HS Id that says for the 2012/2013 school year
A receipt for my classes fees
And my current class schedule
Hope that helps!
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Application Sent: 09/20/2012 to Chicago
Delivered:09/21/2012
Rejected:09/27/2012
Re-Submitted:09/29/2012
Re-Delivered:10/01/2012
G1145 Email:10/04/2012
Routed to Texas
I-797C:10/06/2012
Biometrics Letter:10/13/2012 for 11/02/2012
Walk In Chicago Pulaski:10/15/2012
Approval:11/13/2012
EAD Received:11/16/2012
SSN Applied:11/19/2012
SSN Received:11/26/2012