Depends on what you wear. I have a tattoo on my hip bone, so nobody can see it unless I pretty much take off all my clothes (except for underwear). Basically just think about all the things you wear in front of your parents, and then eliminate the spots that are uncovered as potential tattoo spots.
A couple of suggestions: 1. The ankle 2. Below the hairline on the back of your neck. 3. Breasts & chest area 4. The inside of upper arms 5. On the back of your leg 6. High up your thighs 7. Foot 8. Back of the ear 9. Hip 10. Vertical back 11. Above your... umm lady thing
It depends on what you're wearing with it. I have one on my back and there are so many shirts that show it. If you put it on the inside of your wrist you can wear a watch over it (that's what I'm going to do for work when I turn 18)