Hi Yumi,
Congrats to you for being so proactive about taking supplementary coursework. I find that to be the thorn in the side of many of my clients who wait until the last minute to think about this.
When I applied to HBS myself, I was conditionally accepted (a rare, if not nonexistent anymore, occurrence). I had to take supplementary coursework to prove I was REALLY ready for the Harvard classroom. Additionally, I have recommended that some of my clients who have low GPAs (under 3.6) or little quant experience to take supplementary coursework as well. I recommend you take the following courses if you have not yet taken them and earn a B+ or better in them (in order of importance):
1) Accounting
2) Finance
3) Statistics
4) Microeconomics
5) Calculus
You are right that it is completely fine to take them at a community college. Don't pay a lot more money to take these courses at a fancy institution unless you really just want to do that.
I took Corporate Finance through BYU Independent Study and recommend them if you're interested in online learning. However, a community college is just fine as well.
Good luck with your process!
Kaneisha
Kaneisha Grayson, Harvard MBA + MPA '10
Founder, The Art of Applying®: get into the graduate school of your dreams and get money to pay for it
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