I remember my consumer education class in 9th grade in 1973 making us all do this in front of the class with the teacher playing the customer with students having to make change. We also were put into pairs to simulate being married and given real life scenarios of jobs, living expenses etc and forming a budget and then demonstrating to the class how we survived on the income we had. Now I work with low-income families who don't understand that if they bring home $1000/month, they can't afford $1200/month rent unil I literally show them the math.