I'm not sure what you mean by 'CD thing'. Do you mean the case the game came in or the optical (CD) drive on the computer? If you mean the case it came in, it should open like any standard CD/DVD. Just by pressing onto the indentation on the side with your thumbs and pulling your hands apart.
I'm going to assume you mean the optical drive though. If it is a tray loading optical drive, there should be a small eject button next to the tray that opens it. If you can't find it, you should be able to open it in Windows Explorer by right clicking the icon of the drive, then choosing Eject from the context sensitive menu. You can close the tray in the same manner, only this time Eject will be replaced with Close Tray or something similar.
If it is a slot loading optical drive, there is no need to open it, as the CD/DVD will simply slide into it when lightly pushed in. If it is slot loading, I would still recommend ejecting first, just in case there is a disk in there, so you don't jam the drive up. You can eject this the same way as above if you can't find the eject button. Enjoy your new game and Merry Christmas!
EDIT: Please be aware that Sims 3 University Life may require the original version of Sims 3 to run unless it came with a copy, as I'm almost sure it is an expansion of the original game.
Facebook
Twitter