Christopher17
At first, when I was locked by my parents, it felt kinda strange ... that your parents say to you something along the lines, "Now you can masturbate, I'll be back in ten minutes and re-lock you.". Of course, I soon got used to it, even for usually having only ten (and sometimes even five) minutes, and that wouldn't be the worst thing.
Going to school locked was probably more scary than actually problematic. My cage is small enough not to be visible under jeans, so the only time the cage was seen was at floorball in lockers (but only because my teammate yanked down my boxer briefs as a prank).
The most annoying thing is, a cage will prevent you from masturbating, not magically deactivate your penis. It's normal to get an erection - in the morning, most notably; and when you see a hot girl/guy (and you'll see a lot of them at school). This will, of course, be a lot more frequent, as you're always horny and subconsciously try to find sex.
About your situation, Chris, one of my floorball teammates (Robin) is also locked. His parents are way more strict, and he was released only at the end of each semester if his grades were good. He told me that he actually preferred this, as orgasming and getting back each month refreshes the orgasm sensation and horniness, and that's what drives you crazy. However, I disagree with him in that.
I may have written that I don't get much fun from milking, but that's very relative. I usually try to compare things to an actual orgasm, and therefore milking is like nothing at all. When you compare it to nothing and staying horny, it's definitely better to milk; you empty your balls and the feeling of constant horniness disappears for a while. When it comes back however, it feels (at least for me) that it's stronger than before.