Hi @tsemko,
Now Arduino Create is a very stable platform and have incredible uptime. We invested a lot in stability and we already have good uptime (99.98% in the last year for the first page and 99.95% from a functional point of view of the main components of the Editor, our goal is 99.99% for 2018).
My colleague is writing you too and please tell to other schools we now have a working and reliable solution for all Chromebook users.
Thank you!