In this outdoor activity, learners race small boats, made of cork, balsa wood, popsicle sticks etc., to investigate the rate and direction of currents in a stream or creek. Learners will examine what variables such as water volume, slope of the stream bed, and obstacles such as rocks determine the rate and direction of a stream’s flow. To expand learners’ investigations of stream life, this activity can be combined with the What Lives Here and Hold It! activities from the same source.