I need some advice

Hope you guys can help me make this decision.</p>

<p>I am a student from ghana (africa) who plans to apply to princeton, harvard, yale, amherst, macalester, university of minnesota and maybe a few more schools including some british ones.(Princeton is my 1st choice)</p>

<p>I took my IGCSEs last year in:
Eng, Math, Phy, Chem, Bio, ICT, Dev't Stds, Environmental Mgt and Eng Lit. I got A*s in all but Lit (I got an A in that).</p>

<p>I am currently doing my AS levels in Phy, Chem, Bio and Math and General Paper. Hopefully will get all As</p>

<p>In sept I have to go back to school to finish my A levels in those subjects but I will prefer to take a hybrid 'gap year/home study' period during which I will finish my A levels on my own. ( Will probably take Econ,Hist, Phy and Math) ( I cant do Hist and Econ in my sch cause my classes clash) Assuming that I do very well in them, and get a wonderful SAT score ( 2300+) will the fact that I didnt graduate 'traditionally' affect my applications in any way? esp to princeton?</p>

<p>I hope to do some volunteer work in South Africa/ Teach Eng in Mali/ Volunteer in Brazil/ get a job in switzerland during the year. (or maybe do all)</p>

<p>About ECs ( they're not too many)
1. Head Prefect of school (head of student body)
2. Prez of SRC (Student Representative Council)
3. Prez of Debate Club
4. Member of School Choir (Play Keyboard and Guitar, Vocals)
5. Table Tennis player (havent won any awards)</p>

<p>Will the 'gap year/home study' have a positive effect or not?</p>

<p>Will appreciate all opinions</p>