# The Coordinate Plane, ETC Montessori

Math 9-12

Pull out your math timeline, Descartes is coming!

Simple and engaging, this material has been a successful experience from day 1. We had prior experience with negative numbers, and reviewed our Roman numbers. We knew the terms coordinate and quadrant from our cartology and economics works. We were feeling confident when looking at the coordinate plane.

The first lesson is a story to introduce René Descartes. Who is Descartes again? Standford University describes him as “famous for having made connection between geometry and algebra, which allowed for the solving of geometrical problems by way of algebraic equations.” In France, he is also known for his advanced philosophical ideas on the body-mind symbiotic existence.

The story leads to an interesting statement : take a solid geometric shape, add the number of vertices to the number of faces. Then subtract the number of sides, the difference will be 2. We used what we had at hand, magnetic tiles, to create 3D shapes and try, and it works! How awesome is this?

The objectives of the lessons are:

• Understanding how to graph points on a coordinate plane.
• Using negative numbers/integers within the four processes (+, -, x, ÷).
• writing equations on a line given coordinate points.

The set contains:

• a teacher’s guide.
• 11 sets of nomenclature cards.
• an acrylic coordinate plane board with pegs.
• Task cards (16 cards for graphing points, 18 cards for using coordinate plane and identifying slopes, 10 cards for work on slope-intercept).

There are 2 lessons for age 9-10, and 4 lessons for age 10-11. One of the 4 lessons has 4 presentations. The lessons for age 9-10 don’t require external materials. The lessons for age 10-11 require operational signs, a set of tiles green/gray, a negative number line, and pictures of green/gray skittles.

You will have to make a booklet to go with the nomenclature cards. If you look at the 3 part cards tray, I simply didn’t cut the label for the text in one of the cards. I saved my card for making a booklet. That’s how we are used to working. I really liked the definitions on the nomenclature cards. They are clear and concise. They provide just enough information without overwhelming the learner.

My learner’s first independent assignment was to study the nomenclature cards, and practice writing each visually given point coordinate in the “ordered pair” format –> (-3, 4). This went really well, and she enjoyed learning with confidence.

Voilà ! I can’t tell you more about this material as we only used that much, but I hope you are feeling excited about it as we are. Montessori format fits in any content, and allows children to take ownership of their learning.

## 4 replies to “The Coordinate Plane, ETC Montessori”

1. Thanks for sharing! How is this material in terms of errors?

1. So far so good, surprisingly, but we have only used the first part (A), and the nomenclature cards.