A few educational sites I like:
Vic Firth Education:
http://www.vicfirth.com/education
Percussive Arts Society Hot Licks:
http://www.pas.org/teach/teach.aspx
Snare Drum Exercises:
http://gottrypercussion.com/resources/snaredrum.html
Norm Weinberg’s WebRhythms:
http://www.vicfirth.com/education/features/webrhythms/intro.php
Tiger Bill Free Lessons
http://www.tigerbill.com/drumlessons.htm
Drum Rudiments
https://en.wikipedia.org/wiki/Drum_rudiments