The long and the short of it is that, no a Managed AppleID cannot be used for any ecommerce applications or other services such as Apple Teacher. Apple's idea is to maintain an education focus and thus that means iCloud, iTunesU, Apple Classroom, iWork Colloboration are the only services that can be used with a "MAID" account. 


To use the iBooks or App Store you must use a personal AppleID or create one using your galionschools.org address. It's recommended to use both and sign into the personal or created account by opening the Settings app then tapping on your name shown in the left hand upper corner, tap iTunes & App Store, and enter an AppleID username and password.