History
These instructional materials come from classroom-based research projects designed for general classroom use. The original instructional sequences were developed by researchers Paul Cobb, Erna Yackel, and Koeno Gravemeijer. Erna Yackel and Debra Herndon have collaborated for over twenty years with teachers across Northwest Indiana to support inquiry-based mathematics instruction.
One Teacher's Story
Debra Herndon is a first grade teacher at Winfield Elementary School and a mathematics education teacher consultant in Crown Point, Indiana.
Debra's journey moved from traditional math-series instruction to inquiry-based approaches. Along the way she saw students gain conceptual understanding and mathematical reasoning through collaborative work, rather than through memorizing procedures. The inquiry sequences let students progress at their own conceptual level — and the approach went on to influence how she taught across other subjects, too.