The accounts are standard Google accounts reflecting the school system. They will be fully functional should you want to use them more widely.
Giving parents individual accounts enables the school to use a single sign on (SSO) for many school systems, reducing the number of passwords you need and the number of times you have to log in to the different school systems. You will be able to use the SSO to access iSAMS parent app and portal, KLASS Ops and the improved parent WiFI network.
Having a school email account will make sharing systems and documents relevant to your child and their learning easier.