I tutored maths, and drums for majority of year 12, about 140 a week for like 5 hours? Such good money, i know, but i stopped the tutoring of maths, and kept up with my Drum tutoring, getting 60 a week for an hour and a half. and its easy stuff. Additionally i did get my car in february and thats amazing... and work was right after school, so it was my break time anyway.
It was no problem throughout the year, and it probably drove me to do more work, knowing that i hadn't been working when i was bringing it monneeyyss. but don't pressure yourself, ask if tutoring is worth twice the amount of time (Work and tutoring time) compared to using that time to understand the concepts more, and using the shit out of your teachers...
Good ruck