Kids that would cause issues, most of the time fights during lunch time. Typically, they do this for their own stupid entertainment at the cost of other people's calming meal.
Here comes Elijah and his lunch monkey friends. This is the 4th fight this week, they never stop!
The most commonly-stolen item of weak public-schoolers, especially in lower-income areas where the schools do not put money on a computerized lunch account. At such a school, students have to bring in the necessary money each day to buy their meal, allowing bullies to steal money that they can actually use, as opposed to a check (is it spelled 'cheque'?).
Bearing refrence to the period of adolescent age when nerds would get beat up by the bigger kid for their lunch money. Thus, lunch money as an adjective can be used to describe anything not worth your time, or done poorly.