I had school 8am to 2pm and hardly ever did my homework (min-maxing it by copying, doing it selectively, testing which teachers are strict about it etc., also switched to a bi-phasic sleep pattern to cope with 8am as a night-owl).
It left just enough time to keep making music, learning to program, doing some photography, dabbling in public relations for a non-profit and of course some partying on the weekend. Once I was old enough to write my own sick-notes I would go for walks in woods instead of a double lesson of math etc.
Now that I spell it out, that's a lot, but that's the amount of life experience these kids loose.
And it's not just about temporary fun. It set me up for the further course of my life: Music brought me my best friends, programming was my entry in to a real career and non-profit work set me up to deal with people well, helping me step up to product management. I also had a few wonderful years studying digital art.