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About Us

About Illustrative Mathematics

Get to know IM’s history, mission, and team

Illustrative Mathematics is a non-profit organization committed to creating a world where learners know, use, and enjoy mathematics.

Our highly respected authors craft and deliver high-quality, problem-based core curricula and professional learning resources that help teachers and students excel in teaching and learning mathematics.

The IM Story

Founded in 2011 at the University of Arizona, Illustrative Mathematics is guided and inspired by educators who work in spirited teams to do extraordinary things.

The result is a comprehensive suite of math curricula, designed to encourage engaging mathematical discussion, supported by tasks, lesson plans, and professional learning.

IM 6–8 Math™ v. III  and IM 9–12 Math™ v. I certified by Illustrative Mathematics are available as open educational resources (OER) and free to access by anyone. To be assured that you are accessing the most current versions authored by IM, we created an IM Certified designation that highlights the organizations with whom we have an ongoing partnership. Additionally, the aligned IM Certified Professional Learning is designed to be interactive and engaging to ensure the immersive experience and best practices needed to seamlessly implement the curricula in your classrooms.

First Partnership Leads to Continued Growth

Open Up Resources 6–8 Math 2.0 was authored by Illustrative Mathematics.  Illustrative Mathematics, authored, reviewed and approved all of the content contained in Open Up Resources 6-8 Math 2.0.  OUR 6–8 Math 2.0 is a high-quality curriculum, and Illustrative Mathematics is proud of its collaboration with Open Up Resources, which brought one of the first full-course OER middle school math curriculum to students and teachers across the country.  Please contact OUR for more information about their version of an IM-authored curriculum.

Our Mission

Our mission is to create a world where learners know, use, and enjoy mathematics through curriculum development, professional learning, and administrative guidance.

We collaborate with and provide guidance to states, districts, curriculum writers, and assessment writers to help improve mathematics education.

A Non-Profit Organization

Illustrative Mathematics has operated as an independent 501(c)3 non-profit organization since 2013. We appreciate the generous support of our Philanthropic Supporters:

  • The Bill & Melinda Gates Foundation
  • Carnegie Corporation of New York
  • Chan Zuckerberg Institute
  • Charles and Lynn Schusterman Family Foundation
  • The William and Flora Hewlett Foundation
  • W.K. Kellogg Foundation

Board of Directors



Lisa Carmona Barbara Chow Heather Hill Gregg Levin
William G. McCallumWilliam G.
Cynthia Nava Lisa O'MastaLisa O’Masta Denise Walston
George Zettler

Advisory Board


Diane J. Briars Diana Cano Phil Daro John Ewing
Jean Foster Nicole Neal Jason Zimba Dave Zura

Leadership Team


William G. McCallum

William G. McCallum

Bill McCallum has dedicated his life to helping teachers, educators, mathematicians, and policymakers show fidelity to both mathematical coherence and student learning.

He is an Emeritus Distinguished Professor of Mathematics at The University of Arizona, where he researches number theory and arithmetical algebraic geometry, authors textbooks, and advises researchers and policymakers. Bill’s work as a lead writer of the Common Core State Standards in Mathematics earned him the Distinguished Public Service Award from the American Mathematical Society and the Dolciani Award from the Mathematical Association of America.

As President and co-founder of Illustrative Mathematics, he chairs the Board of Directors where he helps craft the strategic direction of the organization and contributes to the curricula; he also represents IM to funders, at speaking events, and in workshops.

Lisa O'Masta

Lisa O’Masta
Chief Executive Officer

Lisa brings her passion for education and meaningful student outcomes to everything she does.

Prior to IM, she held leadership positions at K12, Inc., McGraw-Hill Education, SchoolNet, eInstruction, and Laureate International Universities. In these roles, she delivered improved customer outcomes, aggressive growth, and operational efficiencies to product management, operations, instruction, curriculum development, and marketing.

Now as CEO for Illustrative Mathematics, she and her team are committed to pushing boundaries, recruiting and developing talented, diverse teams, and delivering measurable positive impacts in math classrooms across the country.

Kristin Umland

Kristin Umland
Chief Product Officer

Kristin believes that all children can learn and enjoy mathematics, and that by coordinating the expertise of teachers, mathematicians, math education researchers, and business professionals, we can help students realize their mathematical potential.

Before joining the IM team, she was an Associate Professor in the Department of Mathematics and Statistics at the University of New Mexico (UNM). After joining UNM with a Ph.D. in Mathematics, she carried out research in mathematics education, taught pre-service and in-service elementary and secondary teachers, and conducted education outreach at the local, state, and national level. A recipient of both the Louise Hay Award and the AMS Impact Award, Kristin’s goal has always been to improve the mathematical and pedagogical quality of children’s learning experiences.

A co-founder of IM, she now serves as VP for Content Development and oversees the development of curriculum and professional learning.

Kristen (Kris) Welch
Chief Financial Officer and Vice President of Finance and Administration

Kris has a deeply rooted passion and appreciation for high-quality education and learning, and a relentless commitment to listen to partners and customers while constantly innovating to meet the evolving needs of the classroom.

At Discovery, she served as CFO for both Discovery Channel and Science Channel; and as Senior Vice President, Global Content Operations, she was responsible for producing and broadcasting programs across 32 networks and 220 countries. In 2013 she was honored with a “Women Leading Women” award from the University of Maryland; in 2011 she was named a “Person to Watch” by The Financial Manager, the magazine of the Media Financial Management Association.

As CFO and VP Enterprise Management for IM, Kris oversees finance, accounting, project management, legal, human resources, and administration. She believes that IM’s impact and success are dependent on its ability to support and leverage its own diverse talent and expertise.

Karl Nelson

Karl Nelson
Chief Information Officer

Throughout his career, Karl has been devoted to delivering high-quality educational materials to students, teachers, and districts across the country.

Prior to joining IM, he served as COO for Open Up Resources where he directed product development and new technology implementations. As Director of Digital Learning for the Office of the Superintendent of Public Instruction in Washington state, he created Washington’s K–12 OER project and served as the state lead for the K–12 OER Collaborative, a multi-state effort to develop open educational resources. He was also lead policy maker for digital education, developing and implementing online systems and providing technical support to districts.

Now the Chief Information Officer for IM, he is responsible for the organization’s engineering, systems, and evaluation work.

Trisha Thomas

Trisha Thomas
Chief Customer Officer

Trisha’s passion for K-12 education has driven her 20-year career working for organizations dedicated to helping learners succeed by delivering the quality content and instructional resources to help them do so.

Before joining IM she served as Chief Marketing Officer for Evan-Moor Educational Publishers, Director at eInstruction, and Manager at Discovery Education. Her marketing leadership earned her a Daytime Emmy Award and a Rising Star Marketing Award.

She now serves as IM’s Vice President for Customer Experience where she is responsible for defining, measuring, and delivering a world-class experience for users and clients. As a parent and advocate for K-12 education, Trisha values the importance of quality mathematics content and instruction in the classroom and is excited to be a part of this work through IM’s curriculum and professional learning services.