Whenever I have a school photo or something I tend to smile without showing my teeth because I think I look weird like that. But whenever I look at my friend's school photo they smile with their teeth and they look great.

You can always try posing in front of the mirror or taking some pictures of yourself from different angles, teeth showing and not and see how you feel about it then. I have a naturally gummy smile and for photos I do prefer only my teeth and not my gums to show which means I have to make a conscious effort to make my smile nice for the film.

It is your smile, you do whatever you feel fine with :)

My smile is just like that smiley at the end lol