Developing concepts across grades

This gallery of selected animations is designed to support learners in their journey to mastery of mathematics—from middle school, to Algebra I, to Geometry, to Algebra II and Precalculus, to Calculus, and Statistics.

These materials build on resources that were first made available by the Dana Center and Agile Mind as part of the Open Education Resources Initiative of the William and Flora Hewlett Foundation, and we are delighted to contribute them to this new audience.

These animations were developed in collaboration with hundreds of exemplary mathematics educators throughout the country as part of a system of programs intended to enable every student to have the opportunity to succeed in learning a challenging mathematics curriculum, supported by a teacher who has access to the most promising practices in instruction and formative assessment. The larger programs are available to schools and districts by subscription. They contain thousands of research-based animations of key concepts, as well as thousands of interactive problems and other resources for teachers and students to share.

For more information on these resources, please contact Kathi Cook at or Susan May at