Ooh @rogersha82, how interesting; I wonder how astute Wazuans would do if they were allowed to participate...
Okay my thoughts are it's a purely short-term play, what with only a 3 month time frame. So ironically, you are required to specultate to 'learn about investments'.
So in my opinion, I'd gamble on shares that are down-trodden or will have some kind of results soon (liquidity - availability of shares is not a concern in the game).
SGL, EXP, CMC, KQ
Note however you have to time your exits carefully. Many transactions lead to more transaction charges. Good Luck.