It was revealed on the January issue of Monthly Shonen Gangan, that Soul Eater manga-ka, Atsushi Ohkubo is launching a new Soul Eater manga running alongside the original one called, Soul Eater Not!. Soul Eater Not! will start on January 12, 2011.
The plot of this new Soul Eater manga has not yet revealed. I think I would let the top pic decide what is the plot for this one.
Source: Kyō mo Yarareyaku via ANN