In one activity that relates to understanding
the structure and function in living systems, “How
We See Things,” competing hypotheses are offered
to explain how we see (Osborne, Erduran, and Simon
2004). The two hypotheses are (1) light travels from
our eyes to an object, and (2) light rays are produced
by a light source and reflect off objects. Students are
provided five pieces of evidence (e.g., light travels in
straight lines) that they use or disregard as they develop
an argument for one of the hypotheses.