Douglas O’Roark, Executive Director

In addition to serving as the Executive Director of MC2, Doug works at DePaul’s STEM Center which seeks to improve math teaching across CPS. Previously he led the Secondary Math component of the UChicago Urban Teacher Education Program and was the first teacher hired at Payton College Prep. He was awarded the Radio Shack National Teacher Award, the MAA’s Sliffe Award for Distinguished Math Teaching, and the ICTM  Rine Secondary Math Teaching Award. Both the City of Chicago Math League and Payton Prep have awards named in his honor. He lives in Chicago’s Andersonville neighborhood with his wife, a mental health researcher at UIC, and two children, who attend CPS.


Katherine DeLisle, Lane Tech Site Coordinator

Katie DeLisle is a mathematics teacher at Lane Tech College Prep High School. She recently graduated from Carthage College in Kenosha, Wisconsin with a degree in Mathematics and Secondary Education. She was also a 4-year member of the Cross Country and Track & Field team at Carthage. She enjoys reading, running, and eating lots of pizza in her free time!

Sara Heiberger Payton Site Co-Coordinator

Sara joined the Payton faculty in 2014 and started teaching for the Payton Math Circle the same year. She transitioned to Site Co-Coordinator in 2015. In addition to working with Math Circle she enjoys coaching the Payton Math Team. Sara graduated from the University of Chicago with an B.A. in Sociology in 2009 and an MAT for Secondary Math Education in 2012. Outside of math she loves to cook and spend quality couch-time with her two dogs.

Benjamin Walker, Payton Site Co-Coordinator

Benjamin loves learning and teaching, and believes that working with young people is as much a privilege as it is an adventure, and that learning math is something best done as part of a team. Benjamin developed his love of mathematics at Miami University of Ohio (BA Math and Stats, BA Integrated Math Education), Eagle Rock School in Estes Park, Colorado, Golder College Prep, and currently Walter Payton College Prep. Particular interests include math modeling, climbing, crossfit, vocal music, and traveling.

Jen Zimmerman, UChicago YSP Site Coordinator

In the fall of 2015 Jen joined MC^2 as the University of Chicago YSP Math Circle site coordinator. Additionally she has served as the Associate Director of the University’s SESAME Program for the past 13 years. SESAME is an outreach program offering Chicagoland teachers courses towards the State of Illinois Middle School Endorsement in Mathematics and Science. In her spare time she also runs a marketing campaign for the University’s Polk Brother Program, another teacher outreach opportunity.

Robin Lam, Bridgeport Site Coordinator

Robin teaches math at George Washington High School. She graduated from Vassar College with a Bachelor’s in Mathematics and from the University of Chicago with a MAT for Secondary Math Education. The easiest ways to get Robin talking in a conversation are to mention hiking, reading novels, or noodles. She lives in Bridgeport and enjoys exploring new restaurants in the area.

Lauren Phillips, Morgan Park Site Coordinator

Lauren has been a math teacher at Morgan Park High School since 2010, teaching a variety of courses and loving every journey she takes with students in the world of mathematics. Lauren graduated from the University of Illinois Urbana Champaign in 2010 with a B.S. in Psychology, and then in 2012 graduated from Northwestern University with a MS.Ed in Secondary Mathematics. Outside of math, she loves boating, movies, traveling, and cooking!

Sara Rezvi, Little Village Site Coordinator

Sara works as a CPS Instructional Coach at the University of Chicago by day and a doctoral student/superhero by night. She teaches teachers how to teach mathematics from an experiential and social-justice orientation and has taught mathematics in grades 7 through 12 in New York City, Mexico, and Chicago. She is currently a graduate student at UIC working on her doctorate in mathematics curriculum and instruction. She is proud to be a part of Math Circles of Chicago and is always seeking to bring the joy of a really good proof to anyone who meets her. In her spare time, she enjoys walking her very silly German Shepherd dog, Jedi, and is an avid reader of science-fiction books.