I am using duolingo to create centers for students. One rotation is 20 minutes on the computer. I would like it if I could receive a tracking notice each week of how many minutes students were on duolingo. Also, I ran into a problem today. Students have discovered the chat feature before I did, and have been using it for some disturbing messages amongst each other. How do I disable this, or at the very least, erase these offensive messages? Thanks for any assistance with this!