VO, i was denied for a F-1 visa today at the US consulate in Lagos, and I'm unsure why that was my outcome.

My interview:

I arrived early and went through the fingerprinting and all. I was interviewed by an older white VO.

vo: how many schools did you apply to?
me: two (told her the two schools-hood college and Lesley University)
vo: why did you pick Hood
me: told her about how good of a program the math education is at Hood, the faculty and all (she didn't even look at me)
vo: when did you finish your undergraduate
me: 2008
vo: what have you been doing since then?
me: served NYSC and I have been teaching Math and Economics at my mum's (sponsor) school going on 4 years
vo: Are you married?
me: No, but I'm engaged
vo: who's sponsoring your education?
me: my mother (proprietress at the school I currently teach) She didn't even ask for proof of funds.
vo: did you take any standardized exams?
me: No, it was waived (GRE waived at the two institutions I applied to because my work is directly related to the MS mathematics education program, and I graduated 2nd class upper from Ogun state university).

At this point she typed for about 1 minute and then returned my visa and I-20 and said she couldn't approve my visa at this time. However, she said I could reapply.

VO, I need your help with reapplying:

How can I strengthen my 2nd application?
I still want to attend Hood college, should I apply and write the GRE anyways though the school waived the requirement? School starts on August 24th and I can book another appointment before then, what should I do? (I don't want to be denied the 2nd time)

Please help,

Thanks,