Check out this database of music lesson plans from Hillsborough Countyu Schools: Music Curriculum Search You will need to enter the provided username and password.
I have not examined these lesson plans in detail, but when you log in you can select the grade and the state standard and it will provide you with a PDF of the lessons they have included in their database that match the search criteria. They have a large amount of elementary lessons, but the database is not limited to the younger grades! I searched and found lessons for both middle school and high school classes. This is a wonderful resource that I believe is meant to be available to the general public and can be a great help to beginning teachers.