Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Early Childhood Education

First Advisor

Dr. Lynn C. Hart

Second Advisor

Dr. Mona Matthews

Third Advisor

Dr. Barbara Meyers

Fourth Advisor

Dr. Keith Wright


Communicating their thinking in mathematics is challenging for young children. This research studied the change in first-grade students’ oral and written solution explanations before and after six problem-based mathematics lessons that focused on developing conceptual understanding of adding or subtracting a 2-digit number and a multiple of ten. A pre/post quasi-experimental design was used. Participants were assigned to a comparison group or an intervention group based on the classroom in which they are assigned. All students completed a pre-and post-assessment. Both groups received the same problem-based lessons. To encourage growth in their communication skills, students in both groups were asked to talk about their strategies, while the intervention group was asked to both talk and write about their strategies during each lesson. Oral and written pre-and post-assessments were scored using a rubric adapted from the Project M3 curriculum (Gavin et al., 2006-2008) and interrater reliability was established. T-test analyses were conducted to determine if a significant difference exists between first-graders oral and written mathematical explanations within discourse modes (comparing pre/post writing or pre/post talking) and between discourse modes (comparing talking and writing) for the intervention and comparison groups. A significant difference between discourse modes was found on the pre-assessments but not the post-assessments, suggesting that increasing oral discourse decreased the gap between the children in both groups ability to talk and write about their thinking. A significant difference was found within discourse modes for the intervention group, but not the comparison group, suggesting that adding written discourse to problem-based lessons further increased the children in the intervention group’s ability not only to write about their solutions, but also to talk about their thinking. ANCOVA analyses were conducted to determine if there was a difference in the oral and written explanations between the comparison and intervention groups. ANCOVA analyses found a significant difference between the comparison group and intervention group’s oral and written explanations at the completion of the study, suggesting that adding written discourse to problem-based lessons increased the intervention children’s ability to both talk and write about their thinking.