I'm in Canada, and my high-school experience was decades ago, but, for comparison's sake:
In my jr. high school (grades 8-9-10) there was only one 'student council' for the school, no individual class officers. As far as I, or anyone I spoke to knew, the chief purpose of the council was arranging and advertising dances and other social events, and encouraging, by their own presence, clubs and sports. It was pretty much one big social activities group, and run by the kind of people who enjoy that kind of thing. The out-going, popular kids. There were 'elections' and such, but in general, once you got on the council, unless you really messed up, you were on it 'til graduation or you left the school. So, you might run for one of the 'lesser' positions in your first year, but by senior year, everybody pretty much knew who to vote for.
I knew one girl who took it seriously - she was smart, diligent, had good grades, but was neither social or popular, and thought the student council should be about actual issues - at the all-candidates meeting, she had an actual platform of reform, student rights, consultation with the school board, and letters to the provincial authorities. Everyone was polite enough not to laugh. She got a few votes from her friends, and some protest votes against the (pre-ordained) winner.
I also knew the winner, she was no wicked 'queen bee' type - she was also smart, diligent, and had good grades, but she was fun, social and knew how to throw a party. Just the unspoken qualities the job required.
I stopped paying attention in senior high school, but I got the impression it was much the same: basically something a kid could stick on a college application.