Mine‘s getting so accustomed to cold showers that I a) absolutely do not mind cold water for swimming etc. anymore and b) could not enjoy warm or hot showers anymore. They just weren’t nice at all.
A. I got to drive a train when I was 9 (a family friend charted a Chicago Elevated train for his graduation party and as the youngest person on the train one of the operators said "hey you wanna drive the train" and so I got to drive the train for a bit
B. I went back to college a few years ago and managed to complete a 2 year degree with a 3.71 GPA while attending college full time, working 20+ hours per week at times as the sole breadwinner while my wife was pregnant with our second child and I had to commute about an hour each way to school and work. I literally started my second semester the day after we returned home from the hospital after his birth. Unlike driving a train I don't intend to recreate that experience ever again...
My sister had to take a final exam at college right after having a baby, my mom held the baby outside for her while she did.
I went to university after having my first set of kids while they were little but wasn't working much. Tried to go to grad school while working full time and parenting and it wrecked my life so completely I didn't think there was any amount of future income that would have made it worth doing. Even now, I can't imagine it.
Yeah it was a pretty rough period of time and I absolutely felt the "work hard, play hard" pendulum swing where as hard as you work you have to relax equally hard, but I tripled my pre-college income in just 2 years (which isn't hard when I was only making $12/hr) so in the long run it worked out but I wouldn't recommend such a grind to others if they can help it