Okay, they have now released OS X 10.10.1 which has fixed a lot of the issues people were having. I have 10.10.1 on my MB Pro and I use Adobe Production Suite CS6 with no problems. I tested imovie and iphoto and they are working fine also.
Yosemite is free so there will be no issues with software licensing. You do not need email addresses to download but you will need at least one apple id. You can down load Yosemite on your computer using your apple id. Make sure when it is done you copy and paste the install file to a different location if you plan to install it on your computer as after Yosemite installs it deletes the install file.
Then make a usb installer of Yosemite for the other computers. Here is a link that will walk you through how to do that:
How to make a bootable OS X 10.10 Yosemite install drive | Macworld
Then boot from the usb, do a clean install on the student computers. You can skip setting up apple id and icloud id during the install. You won't need any email addresses especially if you don't set up the apple and icloud id stuff.
I know it can be a bit overwhelming but try it on your own computer then on one student computer and see if it works the way you want.
And if you get really confident, and if the student computers are all the same, you could even try cloning them from the first student computer that is now all set up with all the appropriate software installed (provided you have site licenses for it all, if necessary.)
I hope this helps.
Lisa