In my middle school curriculum, we are doing 3 units. The first unit is learning to write our own music. For this, I taught a mini need to know theory course and a lesson on lyrics where we analyzed a song and lyrics. I am using Jamstudio and Noteflight to actually write the music.
In order to host the music and grade it, I created a class wiki using wikispaces! This site is so great. The wiki is private and each of my students has a username and password, created by me, in order to access the site.
This is a screenshot of the wiki. The students are listed on their homeroom teacher's page and they post their compositions there. They also email the finished the product to me so I can grade it.