For adults or teens with an oily T-zone on their face; there are lots of cosmetic items that help with oil control, but a very inexpensive item that does the job very well is Milk of Magnesia. A generic brand will suffice and is even less expensive. Just put a cotton ball's worth of the milk of magnesia on the oily areas. Let it dry for a few minutes, and then wipe off. It really absorbs the oil for hours and hours and is very cheap to use!
Wow, that sounds pretty wild! But I guess if Milk of Magnesia absorbs all the yucky stuff in your tummy, it'll take care of oily skin. I may have to give it a try!