Students (n = 1,069) from 60 4th-grade classrooms were taught the control of variables strategy (CVS) for designing experiments. Half of the classrooms were in schools that performed well on a state-mandated test of science achievement, and half were in schools that performed relatively poorly. Three teaching interventions were compared: an…

A crucial element of the logic of the scientific method is the Control of Variables Strategy (CVS), in which conclusions about causal relations are enabled by manipulating a focal variable of interest while holding all other variables constant. Understanding CVS in elementary grades generally is poor, but can be improved with systematic…