We are also working on this process, currently looking at music first and whatever smart music is called now. Look into how your district is splitting up the TIA money. Our district keeps 10% for program administration, giving 90% to the teachers. The 10% is more than enough to cover the cost of either of those systems.

If that doesn't work, I would use a basic music theory assessment. There is an Alfred book that covers music theory basics, there is a teacher reproducible book you can buy. Pick an appropriate level from there, give the kids the unit test during the first week of school, give it to them again in December, compare the scores. For 6th grade that could be a simple notes on the staff assessment. For high school, you might pick something from a later unit that would cover basic concepts of form, Italian musical terminology, maybe labeling some more complex rhythms.