Merlot
Music Tech Teacher - Plans, interactive quizzes/games, and worksheets
Teach-nology Lesson Plans
Teaching Ideas
Edsitement
LessonPlansPage
PBS
Teacher Vision
E-Themes - database of websites
Learn NC
Classics for Kids
Teachers Pay Teachers
Finale and Seblius have worksheets in their programs
Puzzle Maker
Rubric Maker
Music Alive - Lessons and pre-made worksheets
Schrock Guide
Classic FM
Teachers.net
Curriki
OER Commons
EDSITEment
Gooru
Learning Registry
OpenEd
PBS LearningMedia
ShareMyLesson
Smithsonian Learning Lab
TED-Ed
WatchKnowLearn