William G. McCallum (born 1956 in Sydney, Australia) is a University Distinguished Professor of Mathematics and was Head of the Department of Mathematics at the University of Arizona from 2009 to 2013.
He was educated at North Sydney Boys High School.[1] He received his Ph.D. in Mathematics from Harvard University in 1984, under the supervision of Barry Mazur. After spending two years at the University of California, Berkeley, and one at the Mathematical Sciences Research Institute in Berkeley, he joined the faculty at the University of Arizona in 1987. In 1989 he joined the Harvard calculus consortium, and is the lead author of the consortium's multivariable calculus and college algebra texts. In 1993–94 he spent a year at the Institut des Hautes Études Scientifiques, and in 1995–96 he spent a year at the Institute for Advanced Study on a Centennial Fellowship from the American Mathematical Society.
In 2006 he founded the Institute for Mathematics & Education at the University of Arizona. He was Director of the Institute until 2009 and again starting in 2013. In 2009–2010 he was one of the lead writers for the Common Core State Standards in Mathematics. His professional interests include arithmetical algebraic geometry and mathematics education.