School is already a full-time job. You add up the hours, plus homework, and it's over 40 hours a week. They don't get paid for that. The only incentive is someone saying they did good. They are literally forced to go every day. Someone could argue that they're better for it, and they can get a better job, but they overwork them, and they don't teach them to their ability.
On top of that, forcing them to get a job to teach them responsibility? No. Not unless they're doing horrible in school, in which case the parents should buckle down, and send them to a private school that's better at that.
The only case where a kid should be forced to get a job is if they financially have to. Otherwise, leave it to them.
Their grades will probably suffer. If you aren't poor, pay them for chores. That will be enough. Just don't pay them if they don't do them.
@geekpowered exactly what I mean. A job should be a choice by the student if the family is financially stable.