Our Team

John D. Mays

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John serves as Director of the Laser Optics Lab at Regents School of Austin. He has earned a BS degree in Electrical Engineering from Texas A&M University, a M.Ed. in Secondary Education from the University of Houston, a Master of Liberal Arts from St. Edwards University, and he completed 36 hours of graduate study in the field of Physics. John worked as an engineer and engineering manager for 14 years from 1982 to 1999.

John entered the field of education in 1985 teaching Math in the public school system. Since then he has also taught Science and Math professionally in private high schools. He taught Math and 20th Century American Literature part-time at St. Edwards University for 10 years and mathematics at Concordia University. He taught full-time at Regents School of Austin from 1999-2012, serving as Math-Science Department Chair for eight years. He continues to teach on a part time basis at Regents School of Austin.

John is the author of many textbooks and teacher resources. He now works full time as a writer, publisher, speaker, and school consultant.


Kevin Nelstead

Kevin has a BS in Earth Science from Montana State University and a MS in Geology from Washington State University. He earned his teaching certificate from the University of Missouri-St. Louis. His Master’s research involved the study of Quaternary (ice age) volcanic ash deposits in the Channeled Scablands and Palouse Hills area of eastern Washington.

Kevin has several years experience as an educator at private schools both in the United States and internationally. Since 1998 he has served as a Senior Cartographer, Geospatial Analyst, and Natural Resources Specialist. Kevin is a member of the Geological Society of America, the American Scientific Affiliation, and the Affiliation of Christian Geologists. He has four adult children and lives with his wife in Montana.

Kevin is the author of the forthcoming Earth Science text for middle school grades.


Christina H. Swan

Christina received her BS in Biology from Westmont College and her Ph.D. in Molecular Pathology from the University of California at San Diego. She was a research chemist for several years before choosing to become an educator. She currently teaches chemistry at Regents School of Austin. Christina is a reviewer and contributor to Novare’s chemistry curriculum series. She is the primary author of Chemistry Experiments for High School and Chemistry Experiments for High School at Home.

Review Team

Centripetal Press textbooks are submitted to a rigorous review and edit process by our review team. Our books have the advantage of being written by a single author so that students experience the unified voice of one expert teacher. However, many voices are behind each author in the team of reviewer and editors who play an essential role. These women and men are credentialed experts in their fields, and most are also full time teachers in either high school or college.

Not every reviewer contributes to every textbook. Normally 3 to 6 reviewers will bring their services to a book project. They closely scrutinize the narrative for technical accuracy and lucidity. As educators, they also consider and make recommendations regarding pedagogical matters. We love our reviewers and are deeply grateful for their service!

  • Dr. Chris Mack, Adjunct Faculty, University of Texas (PhD Chemical Engineering, MS Electrical Engineering, BS Physics, Chemistry, Chemical Engineering, Electrical Engineering)
  • Chris Corley, Department Chair, Regents School of Austin (MS Computer Science, BS Geophysics)
  • Dr. Christina Swan, Chemistry Teacher, Regents School of Austin (PhD Molecular Pathology, BS Biology)
  • Cathy Waldo, Science and Mathematics Teacher, Regents School of Austin (BS Physics)
  • Dr. Steven K. Mittwede, Earth Science & Theology Teacher, Providence Classical School, Spring, Texas (PhD Geology, MS Geology, BS Geology, EdS Candidate Educational Leadership, MTh Modern Evangelical Theology, MA Intercultural Studies)
  • Dr. Ron J. DeHaas, Consulting Petroleum Geologist, Michigan Basin and CEO, Covenant Eyes, Inc. (PhD Geology, MS Geology, BS Geology)
  • Dr Jorge Munoz-Burgos, Physics Teacher, recently returned from position as Associated Research Scientist, department of Physics & Astronomy, Johns Hopkins University, on assignment at the Princeton Plasma Physics Laboratory, Princeton NJ (PhD Atomic and Plasma Physics, MS Physics and Space Sciences, MS Electrical Engineering, BS Electrical Engineering and Communication Systems)
  • Dr. William Howard, VP Engineering, JP3 Measurement, Austin TX (PhD Physics, BS Physics)