In High school, we were given an assignment on household budgeting in Social Studies during Senior year. We were able to choose any profession (teacher approved) and created a list of monthly expenses based on average starting salaries. You should have seen the crap everyone bought. Even with about $1000/month limit, the lists included gaming systems, designer clothes, luxury cars, etc.
I don't think it's just about teaching kids how to budget their money, They also have to face that moment when they need cash for a necessity and there just isn't anyway to get any more. The reality is that people get in trouble financially because they max out their monthly allotment without leaving room for emergencies. How many times have you heard someone say they can afford "$$$$ per month" instead of looking at the total price?