I wish there were more young boys with your mindset out there. You are absolutely right for wanting to wait. You definitely don't want to do anything that either one of you will regret later on in life. Even if you are practicing safe sex, I don't believe that anyone at such a young age is ready for the emotional roller coaster that goes along with having sex. Your girlfriend may THINK that she wants sex now due to what she thinks everyone else her age may be doing; but believe me, there's a very good chance that she may experience feelings of guilt & depression afterwards. Even if she absolutely thinks that she's ready, there's a greater chance that she just isn't. She won't know that she isn't ready for sex until after she has had sex. At that point it may be too late. There's a good chance that she could have feelings of resentment towards you.
The best bet it to wait it out. There are so many more activities that the 2 of you can do together. Show her a great time on the dance floor or take a romantic stroll in the outdoors in the evening. Even sharing great laughs at a local pizza parlor & movies with mutual friends will help strenghten your relationship & most importantly, the bond of trust between the 2 of you. In time, after years of a strong foundation, sex will come naturally with nothing but positive feelings for you both.