Choral Public Domain Library (CPDL) is a wonderful repository for music in the public domain. Seek and you will find many gems!
ACDA-MN Tried & True Pieces for Middle School-slides
Master list of Tried & True Pieces for Middle School (170+). Those highlighted consider first.
Public Domain pieces I have used with middle school-will keep adding to the list
Kangding Love Song information
Path to the Moon is a beautiful song for children, but the tessitura is a bit high for changing voices so it isn’t on my list.
Orff Schulwerk Volumes 1-5 are an incredible resource for children’s choirs.
Soli Deo Gloria by Paul Kickstat is on cpdl.org buried in a canon collection, but this link takes you there quickly.
Cantate Domino by Jésus López Moreno
Vo pole berjozonjka stajala (Little Birch Tree) arr. for SATB by Jens Klimek
Psallite by Michael Praetorius
Come Ye Sons of Art by Purcell
Da Pacem Domine (link through cpdl.org)