marking period 1...confused

Its the last week before the the first marking is over and honestly i have to say that i really have no clue what i am being taught.Its not that the teachers aren't doing their jobs .I just don't know what it is going on with me personally . Everything that i learning now I've been taught before. you would think that it would be easier but it not.Its really sad because I'm already lacking and its only the first marking period.So i need to make it my mission to update myself in all my classes , hand in any all that i am missing an work hard to become a better academic learner in school.