SAT2’s are either mandatory or “recommended” by most of the highly selective colleges, so in terms of relative importance, I’d rank them higher than AP tests which are self reported and optional. There are various good commercial study guides for those. Also make sure you have your letter of recommendation teachers lined up. Note that MIT wants 1 LoR from a math or science teacher and 1 from a humanities/social science/language teacher. Use this summer to get ahead on various portions of your application. Note MIT is not a Common App school. Essays and short questions may vary from year to year, but they usually follow common themes. You definitely should gather and fill in the various background info required in the Common App and other application forms. In terms of match/safety schools, a good option will be state flagship honors programs. Many of those operate on a rolling admissions basis, and scholarships are also usually granted on a rolling basis. Have those ready to fire off in the late summer/early fall when applications can be submitted. Consider if you want to ED or EA any schools on your list. There are pluses and minuses to both, but I would definitely do one of those. ED usually provides some admission boost (varies by school, MIT not so much) but it limits your choices especially if FA is important. EA/SCEA little or no boost, but you retain flexibility. Both ED and EA can either narrow the number of apps you will have to submit and can allow you a stress free second half of senior year (if you get in) or can provide you some feedback on the strength of your app if you are deferred or rejected.