Connect With Music
http://www.connectwithmusic.org/

LilyPond that handles the messy job of transcribing music notation. Lilypond handles anything from a simple one-line melody to a symphony or oratorio. That includes not only basic things like lyrics, accidentals, and multiple staves, but polyphony, divisi lyrics, expressive marks, grace notes, instrument-specific notation, scoring for bagpipe, and ancient notation.

MusicTheory.net teaches students how music works. They can do drills on notes on the musical staff, the piano keyboard, the guitar fret board, or valves for brass instruments.

Metronome Online is exactly what it sounds like, and you can adjust it from 40 bpm to 208. To go with the aforementioned annoying clicks, it's also got a grating "A" tone for students to tune their instruments.

Synthesia Notes fall from the sky over a keyboard at the bottom of the screen. Press the correct keys at the correct time to boost your score. Pretty simple.

Music Tech Teacher - Students learn to read, write, compose and publish music. The site includes quizzes, resources, and in-service notes for teachers interested in using technology to enhance music education.
http://www.musictechteacher.com/

Children's Music Portal
http://www.childrens-music.org/childrens-music/teachers.htm

Classics for Kids
http://www.classicsforkids.com/

Music Through the Curriculum
http://www.philtulga.com/index.html

Music K8
http://www.musick8.com/

Music Teacher Resources
http://www.edu-cyberpg.com/Music/classres.html

Music Teacher's Chatboard
http://teachers.net/mentors/music/

Printable Songs
http://www.teach-nology.com/printables/songs/

Music Online
Patriotic Music
http://www.ajsmidi.com/patriotic/usasongs.html

Lessons and Projects
Music that Mimics Stormy Weather
http://artsedge.kennedy-center.org/content/3358/index.html

Build your own instruments
http://www.wannalearn.com/Crafts_and_Hobbies/Woodworking/Building_Musical_Instruments/

Misc.
Music Bulletin Boards
http://www.musicbulletinboards.net/


Twelve Benefits of Music Education
http://www.childrensmusicworkshop.com/advocacy/12benefits.html