a lot of it is in the teacher too.
for example my freshmen year in highschool, my teacher was a complete dousche bag and made no effort to help us or show simple formulas. Basically he was a waste of my oxygen.
My sophomore year i had geometry. My teacher kicked ass, she was dedicated and i knew the stuff so well it could make your head spin.
Last year i had another dousche bag teacher for algebra 2, needless to say he was very similar to my fresmen teacher, and since i didn't know shit from that class, he said it was my own fault that i didn't know what i was doing because i didn't know basic freshmen algebra.
seriously some teachers are so dedicated, and that's how they all should be. They should enjoy what they do and helping people learn. If they're just there to recieve a pay check then they shouldn't be teachers. that's my 2 cents.