Will this damage my macbook pro

Hi guys, I bought this macbook pro 15 inch i7 2.3 ghz for college in a few months. I wanted to also play a few games on it, (call of duty modern warfare 2, Left for Dead, ect..) My dad saw me installing steam, and he got upset, saying that he doesn't want my mac to be screwed up for college. He reminded me that I will be needing to store all my projects and info on this mac, and if it gets damaged that is a lot of money that will be wasted, and time. He doesn't think I should play games on here, because he is worried it could possibly do something to the computer before college rolls around. Do you guys think this would be an issue? should i still install them? Im worried he may be right, but I really wanted to game a little bit before college started.. Ill probably just delete the games during college.