Carefree attitude, unable to study and concentrate in school

My problem is that how can i change my habits of being always disorganized, disoriented. I am a student and believe me that in the last 5 years of my high school, i think i had mentally attended less than 10 percent of the classes. the problem is that i just could not study.my whole trend towards school was extremely carefree. well i have always so many things to do but i just dont do them even if i have nothing to do. i would prefer watching tv even if nothing good is happeneing on it.
i just cant study with concentration. i just cant!!!
i took an iq test with all my concentration, solving 38 questions in 13 minutes on the internet and my iq score was in the 130's . though i was unhappy with the result but only less that 3 % people actually get any higher. on second day i took another iq test with the same frame of mind with which i take my tests and it was 96, below average. i do very well in tests in which i dont have to study. i have always won any quiz that i have participated in. my articles started printing in the most widely read newspapers of the country(pakistan) since the age of 16. at 17 i was the academically youngest participant EVER to be selected in the national physics contest. my physics paper on big crunch theory was selected in a conference in ukraine when i was 18.
i know i have the potentials to do far greater but i just dont pursue anything. my results in college are above average but those better than me or those who top are not mentally better, not at all. they just study hard and i dont study at all!!! i prefer doing nothing, lying around. believe me i would had been able to achieve far greater laurels if only i could have worked harder or at least just worked!!
i am sick and tired of foolish people topping in exams. i am 19 now and i will start my bachelors now. what should i do start working.?