Art, meet geometry. Geometry…Art.

Alzar School | 17.12.14

Most of us think of compasses as those boyscout doohickies that point North.  Some folks think first of the pointed tools that help you draw a perfect circle and get confiscated by TSA.  We use both extensively at the Alzar School, but only the latter comes into the geometry classroom.  At first, it seems like all a compass is good for is drawing circles of different sizes.  But the circle has a particular property where all points on the curve are the same distance from the center.  This technical definition, paired with some creative strategies, has let us create an awful lot more than just circles in our geometry class.

Compass constructions have been a recurring topic all semester and the compass has become a tool for students to explore all sorts of relationships between angles, lines, triangles, and ultimately larger polygons.  Without having to use a ruler to measure distances or a protractor for angles, students have learned to make perfect angle bisectors, parallel lines, perpendicular lines, and find segment midpoints.  With those tools, we’ve been able to make perfect equilateral triangles, squares, hexagons, and then elaborate compound shapes, like triangles inside of circles and circles inside of squares.  Recently, students embarked on a free-lance project and use a compass and straight-edge to create some sort of fun design.


Alice made a yin-yang


Valentina made a 12-petaled flower with overlapping petals and some interesting symmetry


By popular request, I made the Deathly Hallows symbol from Harry Potter.

Then the students informed me it was all for nothing, Harry had used horcruxes to defeat Lord Voldemort instead.

-Dan Thurber