We provide Web VPython (previously named GlowScript) at no cost to users. Users need to use a Google login to be able to write VPython programs, which are automatically stored in a Google database that we pay for, along with paying for the web site. We don't make any use of the Google account names of Web VPython users, and users can mark their folders as private.
We do not have the resources to address the problems this environment raises for some educational institutions, though we do have long-range plans to make it possible for users to use their own file storage if they wish.
An excellent alternative is the commercial site
trinket.io which offers Web VPython (among other languages). See
https://trinket.io/schools for the details on the very low cost of their services. Happily,
trinket.io makes it remarkably easy for teachers to view and comment on student programs. We have used
trinket.io in our own teaching. The
trinket.io developers are familiar with the issues that concern you and are able to address them.
We have no commercial relationship with
trinket.io; the Web VPython software is open source and
trinket.io is welcome to use it.
Ruth Chabay and Bruce Sherwood, developers of Web VPython