Average size for an adult is 5 to 6 inches when *erect*, so I'd say you're doing nicely. ;-) Of course, there are two kinds of men: "grow-ers" (starts small when soft, but much longer when hard) and "show-ers" (starts off the erect size, just moves upward when erect). 5 inches is a respectable "show-er", but if you're a "grow-er", you may need to ask the lovely ladies (or whichever gender rocks your world) to stand back a bit... If you want to help your penis "be all that it can be," the soft tissues in your penis benefit from getting blood in them. Twice a day, give yourself an erection and maintain it for a few minutes. You don't have to ejaculate, just let the tissues expand with blood and maintain that state for a few minutes (using whatever means you are comfortable with). This will get nutrients to all of your internal soft penile tissues and help them "be all that they can be." This is also a good thing to do all your life, to help avoid "erectile dysfunction" when you get a lot older. Contrary to what your gym teacher may have said, your penis benefits from "activity" like any other part of your body. Unlike what your friends might say, you don't need to ejaculate (neither masturbation nor sex), all you need is that twice-a-day three minute erection to maintain your penis' soft tissues.