I have a couple ideas, if your interested. =)
1) Babysitter / Rebellious Teenager
One night, when Jenny Lockwood's parents are out, she decides to throw a party. Her parents come home early, at the height of the party.
The next time they go out, they decide to pay the nerdy man next door to babysit their rebellious teen daughter. Said boy, as it turns out, may not have been the best guy to keep Jenny out of trouble...
2) Teacher / Schoolgirl
Pretty standard and self-explanatory.