Malcolm conducts design research into the theory, development and evaluation of collaborative teaching situations in mathematics education. Glenda Lappan is a University Distinguished Professor in the Division of Science and Mathematics Education. Her research and development interests are in students' learning of mathematics, mathematics teachers' professional growth, and change at the middle and secondary levels. Glenda is Co-director for the Center for the Study of Mathematics Curriculum and served as President of the National Council of Teachers of Mathematics.