Before the first intervention activity, I taught students about simplifying algebraic
expressions with fractional coefficients (section 6-5). During the 6-5 activity I had students read
the example problem
3
5
6
43 xx
+
+
. Then they were given two explanations that explained how
and why to solve the problem (Appendix 2). I wanted students to see how one could explain how
to solve a problem. Students answered questions and judged which explanation was better and
explained in writing why they thought it was. Students then talked with an assigned partner and
discussed their answers. When I was observing, I saw that students were choosing the shorter
explanation as the better one, saying that it was clearer. Since I saw this as a skewing variable, I
made all the explanations the same length for the next activity.