Hello,
Creo 3.0 Academic can't open any Creo 5.0 files. The only possible way is to install on your home computer Creo 5.0 (this will not affect your Creo 3.0).
You will need to uncheck during installation the Creo 3.0 license in the Creo 5.0 installer (licensing window) and use the code for Creo 5.0.
Thanks,
Alex