First i will say my frnds what actually my parents told me. then go to my parents and ask them the reason for not sending me. The common replies from parents would be:-
1) you have your exams nearby wont you complete your portion
2) you always chill out with your frnds and never talk to us
3) i don't have money to waste right now for you.
4) you have enjoyed enough of freedom now sit and study OK!!
5) How will you return
This happened a million times with me so i said with experience.
My parents told me a crore times the same things but tried my best to convince them but it was never possible