This is an awesome list of resources for elementary music teachers, and it includes a link to a freebie! This list would be especially helpful for elementary music teachers in their first 5 years of teaching or those returning after a period of absence!
Books You Need in Your Music Classroom - Upper Elementary List
Lap Packs are inexpensive ways to get students writing in music class. Customize them to include exactly what your music students need. This article has some great ideas for their use and FREE downloads!
Goin' to the Ocean: Orff, Instruments, Rhythm and Composition