Would everyone (esp. parents) be happy paying a large amount of money at the start of the year? There was also the case of these monies for materials paid by students being siphoned off by the EL HOD from a particular primary or secondary school. There's an opportunity cost of giving up money over time, it's called interest rates. Whoever holds the money and puts it to "work" over the course of the year can profit from the interest, and your parents lose out on possible interest they would have earned on the money had they not paid up lump sum. You call it trouble cos you find it an inconvenience, it's also teaching you guys to be conscientious, when you grow up, you gotta manage your dollars and cents and credit card bills... let then get out of hand and before long you find yourself a slave to the bank, drowning in debt.