Karen Karp, is a Professor at the School of Education at Johns Hopkins University where she works with doctoral students. She recently completed twenty-one years at the University of Louisville as a Distinguished Teaching Professor in Elementary Mathematics Education and is a Professor emeritus. She has more than 25 books written on elementary mathematics education including, Elementary and Middle School Mathematics Teaching Developmentally (with Van de Walle and Bay-Williams). She also has written more than 45 articles including her article with Bush and Dougherty in Teaching Children Mathematics entitled “13 Rules that Expire,” named by the journal as article of the year in 2015. She is a former member of the Board of Directors of the National Council of Teachers of Mathematics and a former president of the Association of Mathematics Teacher Educators. During her time on the NCTM Board she was funded by NSF to explore ways to bring the mathematics education and special education communities together to teach mathematics more effectively to students with disabilities.