Three Ring is a neat student portfolio site. Teachers create a class, add students, and then can use an app on their smartphone to capture photo, video and audio files of student work and put them in the child's portfolio.
Today's Meet allows teachers to create a backchannel for students. You create a room, allow students to join, assign someone to monitor the backchannel and allow students to ask questions, or comment as the lesson is taking place. This is great for students who are shy or are able to express themselves better through writing.