How to clone user accounts via Apple Remote Desktop - Mountain Lion
I don't have a experience with OS X 10.8, but I've done plenty of computer-lab admin work back around OS X 10.3 / 10.4 / 10.5. I'll edit and/or remove my answer if better answers come along.
I'd venture that your basic application preferences -- for browsers, word processing apps, etc. -- will duplicate OK (with the notable exception of certain licensed software, i.e. Adobe CS Suite, Filemaker Pro, etc.) -- but probably the Parental Controls settings live outside of user home folders, somewhere under /Library (the System-level /Library, not ~/Library.)
You may have success hand- or scripted-copying the relevant directories and files from /Library, but there could be other issues lurking.
I have little doubt that, without a lot of toil and expertise on your part, your students are probably going to "tear the machines up" software-wise. You'd better have an easy method for wiping & refreshing machines on a regular basis if you want to keep a semblance of consistency.
It'd be much better to run OS X Server 10.8 and use the workgroup-management features built into it, that would give you a robust, easy-to-manage setup.