How to play music in class?

Okay well i dnt have an ipod just an Ipad which is bigger and harder to sneak with. In math the class that i cant ever pay attention to, i bring my bag and all my stuff is in there so i thought maybe putting in my bag and try to bring it close to me then play my music and all with my earphones. Oh so you know my teacher isnt those type to ask many questions or do this activities she just talks and talks and dont notice me much. But anyway i cant hold my bag all the time so when i put it down i feel like shell see the earphone thing on my body. Or i thought just to put it in my desk real easy and all but i feel like something will happen, but if thats good any more tips and advice to make sure she dont notice? And DONT ( like most peoole ) SAY NOT TO DO THIS either because its wring or too big or whatever but i just want an answer!