Ive got some important exams coming up and im just gonna be really busy now so what should i say to quit my saturday (voluntary) job?
You just ask to speak to your manager, and when you are alone with him/her, tell him your reasons. Which you stated in your question, and are entirely valid reasons. Don't be rude about it, you can always use this as an experience in the future or a reference. Make sure you give two weeks notice and you will probably need to hand in a letter of resignation.
Just go face to face with your manager and tell your manager you want to quit. Your manager will probably ask you why and you need to say why. The best thing to do is be honest and kind about it. And don't tell your manager right before you quit give notice before hand like LookinThruMemories said.
Just tell your manager exactly what you told us. "I've really appreciated the experience of working here, but the truth is I am really busy and need more time to study for exams".
Its best to give 2 weeks notice but tell them the same way u posted
Slap him and yell I QUIT