DG-group lessons were significantly better designed for conjecture-to-proof progression and used dynamic features far more than control lessons, while other observed teaching aspects did not differ significantly¶

Claim · All claims
Evidence · 1 study · causal r2 · q3
Currency · newest study 2015 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? Mixed-effect ANOVA on observation data showed significant differences favoring the DG group on Good lesson design (2.81 vs 1.85, p = .032) and Use of dynamic features (2.75 vs 0.70, p = .000). → Jiang et al. 2015 q3 i? On the remaining DGOP/CGOP aspects (actions beyond software, cognitive demand, teachers' knowledge, conjecture/proof, engagement and discourse) the groups did not differ significantly, though all DG ratings were higher. → Jiang et al. 2015

Evidence¶

Jiang et al. 2015¶

Zhonghong Jiang, Edwin Dickey, Alexander White, Ewelina McBroom, M. Alejandra Sorto, & Alana Rosenwasser. (2015). A Dynamic Geometry-Centered Teacher Professional Development Program and Its Impact. Proceedings of the 37th annual meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education, East Lansing, MI: Michigan State University. https://eric.ed.gov/?id=ED584322

q3 · i? · causal · r2

DGOP/CGOP observations in 16 classrooms (8 per group), each visited by two observers four or five times across the school year, analyzed with mixed-effect ANOVA (Table 1). Good lesson design: 2.81 vs 1.85, p = .032; Use of dynamic features: 2.75 vs 0.70, p = .000; overall DGOP 2.28 vs 1.68, p = .088.

"Results confirm the efficacy of the DG treatment by showing significant differences in the two aspects related to the intention to implement a dynamic lesson. As a whole, lessons in the DG group had a significantly better design aligned with the DG teaching approach"

Discussion¶

Related Claims¶

• Students of DG-group teachers scored significantly higher on a geometry achievement test than students of control-group teachers (p = .002), with effect size .45 and a larger effect at the Regular Geometry level — related
• A weeklong DG-centered summer institute improved teachers' conjecturing-proving knowledge, with a statistically significant average gain of 1.37 points (p = .003) — related
• Geometry content knowledge growth did not differ significantly between treatment and control groups despite a significant main effect of time — related