Have you done what is necessary for the trip?
Vaccination? Things to bring? Individual contribution for your group?
Flight details? Passport details?
One of the most important things is also to leave emergency numbers behind for your parents. For eg, have you left behind the school's number, teachers' emergency numbers? It is also important to assure your parents that you will give them a call on which day of the trip etc.
Let's make it worry-free for your parents.
See you at the airport punctually!