Actually I don't think that school on the weekends is such a bad idea.
I'm sure that lots of students would rather go to school on saturady or on saturday morning and get a week or a fortnight extra holiday.
When it comes to schools if I were allowed i would take apart the school day and totally rearrange it. I would have one lot of students start at 7am and go until 12:30 and the the next lot start at 13:00 and go through until 6:30. That way children could have afternoons or mornings free. If classes in one subject were longer and on the same day then teachers could work longer days when they worked but have more days off.
I'd make saturday a school day too so everyone could have longer holidays.

Sometimes I think we're too attached to the ways that we did things when we were younger and so we just keep doing things the same way although there are more efficient ways. Like the keyboard - the a is in a silly place for such an oft used letter but because the qwerty system was efficient for early typewriters we still use it.