What Microsoft is saying is that they're limiting OneDrive accounts to a max of 100GB, but that comes from the 100TB of pooled storage for students since those

What Microsoft is saying is that they're limiting OneDrive accounts to a max of 100GB, but that comes from the 100TB of pooled storage for students since those accounts are free. Faculty accounts (A3 or A5 licenses per a link posted by someone else) will add an additional 50 or 100GB of space since the school is actually paying for those licenses. And schools can buy additional storage in 10TB blocks. Clearly it's primarily a cost saving measure, and I suspect it will be a significant change for some schools, but I suspect the numbers chosen were based on what most schools are using.