These six Chess.com lesson plans provide the curriculum for an improving chess player. Following all of the instructional lessons in each of these links combined with regular tournament play will elevate your skill to around USCF 1400.
Chess.com has an introductory article to their curriculum at this site:
I suggest doing these plans in a slightly different order. Order is not critical either way as long as you do them all.
Is this alot of work? The answer is, "yes." But getting to be a top level chess player is no different than any other skill. Natural talent is enough to get you started, but that will never let you achieve greatness. Hard work is the only proven formula for success. Do you play a muscial instrument or play club sports like soccer, baseball, or softball? Add up how many hours a week you practice and play and compare that to chess. Expect the same results for the same amount of work. If you want to be successful at chess (and by this, I mean at the top of your class) you must make it a HABIT to study, practice, and play chess competitively. Good luck. Only you will limit what you can achieve.