Confused! I Need Help! :/?

So, I applied for NYC Summer Youth Program ! I start next Friday and i'm happy I have a job. I really found good guitar lessons for $30 a lesson. Every two weeks i'll be payed like $300. My friends think I should wait when I'm 16 and have a part-rime job and will be able to get more lessons. But I rather do it now because I really want to learn guitar. My friends think I'll be waisting my summer and I think I won't be. Any suggestions?