Many schools use Google's free products for email, chat, and document management, but kids utilize them for social reasons as well. You're in luck if you want to keep an eye on their school accounts because Bark provides this service for free.
Make contact with your child's school and inform them about Bark Schools. See if they are interested in participating. The bark is used by around 1,300 school districts (and counting) to keep track of their pupils' online activities.