St. Michael's
A Resource for Orthodox Elementary Education
Santa Rosa, CA

Key to Geometry

Several years ago we came across a publisher called Key Curriculum Press. They publish curriculum on a variety of math topics, including a series of non-intimidating, almost newsprint, 55 page books. The topics include measurement, metric measurement, fractions, decimals, percent, algebra, and geometry.

We used the algebra series for a few students who needed a “softer” approach, but we used the geometry for everyone. Never had I experienced children asking for more math homework, but that is what happened with the geometry series, called Key To Geometry.

This is not the geometry you may have had in high school. This is the geometry that Archimedes, and other ancient Greeks, experienced. The whole series is based on what might be called the “guided discovery” approach. It is a construction approach, not a proof approach. The children are never asked to prove anything, but are beautifully guided to discover the principles of geometry. Our students loved it, and I am serious about them asking for more.

The entire series of eight books is completed with 1) a pencil, 2) a compass, and 3) a straight edge, (image a ruler without any measurement markings).

The first six books are 55 pages long and cover:
      1- Lines and Segments
      2- Circles
      3- Constructions
      4- Perpendiculars
      5- Squares and Rectangles
      6- Angles

The last two books are about 150 pages long and cover:
      7- Perpendiculars and Parallels, Chords and Tangents, Circles
      8- Triangles, Parallel Lines, Similar Polygons

We started our students with book one in fourth grade. By the time they had finished the eighth grade, they had completed the series. Geometry was not actually a main topic of study, but the children loved this course so much that we found a way of working it into the schedule.

Each book includes a “Practice Test”, but the students found the tests too easy. Actually, they were a bit insulted because the tests were so easy. In response we made up our own tests which were more challenging. If anyone is inspired to use this curriculum and is interested in these tests, simply contact us at and we will send them to you, at no charge, as PDF files.