Should Teenagers Work in Partime?

Teenagers, in many schools around the world, work in partime jobs. However, is it really a good idea for the learning of the students?

On one hand, it's true that if teenagers go to school only during the morning, they have all the afternoon to do homework, to prepare presentations,... and for their friends, too.
In addition, that is better for people who live far from the school because they don't have to do two travels if they can't pay for the dinning room of the school.

On the other hand, it's a fact that it is worse for students and teachers because if you do 6 hours of class, you will be more tired and exhausted than if you do only 4 hours, after you have lunch and finally you do 2 hours more.

In conclusion, I think that the advantages of working partime are greater than the disadvantages and this is the method that I like to use.