well ive found out a way to do so. idk if this works for everything, but i use this way to play jibberish, so lets use that as an example.
so when you download the jibberishgame file, dont click save when it prompts you to either run or save the app, click run. when the file downloads, it'll run the install setup. click next a few times until you get to the part where it asks where you want to save the installation- dont save it to its default spot, which will be like program files or something. make a new folder on your desktop and install it to there. once its installed, open the folder. click "jibberish.exe" which will launch the program, and you'll be playing jibberish at school.
hope it helps. =]
