Tye03
I am only 23, so not that much older than you, and here is what I did:
I went out and bought one of those stability balls and some 5 lb dumbells and I use those along with some videos to do my work outs. Crunches are very effective when you do them using the ball (not that they aren't otherwise), but they say that it works them harder on the ball because you are trying to keep yourself on the ball and you have to hold your inner core (stomach muscles) in order to balance yourself, so when you do your crunches, you are working your stomach area that much more. I know that is why my stomach is shrinking, but everyone is different.

Just my two cents. Good Luck! If you have any more questions, feel free to ask! I am here to help and get help too
FrogGurl