He’s right. Part of this is because they don’t have working role models, but part of it is because they live in devastated neighborhoods (let’s not get into exactly who devastated them) and there aren’t any of the little jobs we used to do when we were kids - shoveling snow, walking dogs, paper route, delivering groceries, etc.
So the idea of giving them some useful work they can do at school, where they have to go every day anyway, is a good one. Kids at a certain age love to work and they love to show how responsible they are and what a good job they can do - and get praised and compensated for it. That’s what builds good work habits.
One of the reasons it’s hard for poor adolescents, particularly blacks, to get hired is by the time they are teenagers, they have developed absolutely no work habits and employers know that things like showing up on time, staying for a full shift, doing a job well and cooperating with coworkers are going to be things that are completely unknown to them, because they’ve never even done the basic kid-jobs before.