Google Docs has become more popular among children in school settings. It is being used for schoolwork, homework and even class projects. In its original state it doesn’t contain any content as users create their own content or upload it from elsewhere. So in this context it appears safe.
However in recent times children have started using Google Docs as a communication hub. Users are inviting their friends to collaborate on one document. This transforms an innocent piece of paper with typed text into one large conversation with many users. There is no limit on the amount of people that are invited into the conversation. It can’t be clear who exactly is typing. Each user is represented by a small avatar in the top right hand corner and their cursor will match the colour of their avatar.