Authors & Presenters

Mark Onuscheck is director of curriculum, instruction, and assessment at Adlai E. Stevenson High School in Illinois. He is a former English teacher and director of communication arts.

Gib Ostheimer is a high school principal in Wyoming and a former elementary school principal. He has worked with schools on topics including assessment architecture, instructional agility, and school improvement and culture.

Jeffry Overlie is an International Baccalaureate coordinator for Fridley Public Schools in Minnesota. He also works as an adjunct professor of education at Bethel University.

Douglas Reeves, PhD, is the author of more than 40 books and more than 100 articles on leadership and education. He has twice been named to the Harvard University Distinguished Authors Series and was named the Brock International Laureate for his contributions to education.

Anthony Reibel hails from Adlai E. Stevenson High School in Illinois and is the current assistant principal for teaching and learning. Anthony is also coauthor of several books: Proficiency-Based Assessment, Proficiency-Based Instruction, Proficiency-Based Grading in the Content Areas, and Pathways to Proficiency which explore the relationship between proficiency, pedagogy, and evidence-based grading.

Samuel Ritchie is a consultant with 35 years of experience as a practitioner. For most of those years, he was the director of technology at Adlai E. Stevenson High School in Illinois.

Tom Schimmer is an author and a speaker with expertise in assessment, grading, leadership, and behavioral support. He is a former district-level leader, school administrator, and teacher.

Sarah Schuhl specializes in professional learning communities, mathematics, assessment, school improvement, and RTI. She has been a secondary mathematics teacher, high school instructional coach, and K–12 mathematics specialist.

Rea Smith is an elementary mathematics and science curriculum specialist in northwestern Arkansas. She passionately supports the work of professional learning communities with a focus on common assessments to improve student and teacher learning.

With over 30 years of experience in K–12 education, author and education expert Jeanne Spiller is an associate with Solution Tree, supporting schools and districts through workshops, coaching, and collaborative initiatives to enhance instruction, foster innovation, and promote equity.