Using the Geoboard

triangles

Henri Picciotto

The geoboard provides a nicely constrained environment for mathematical exploration, and lends itself to many activities where students can discover or apply important ideas in the K-12 curriculum. This page is a hopefully comprehensive list of links to geoboard activities on this site and on my blog.

All activities I link to below can be done on the CircleTrig Geoboard, a two-sided manipulative I designed. On one side, an 11 by 11 traditional geoboard. On the other side, a circle geoboard, with radius 10 cm, and a 360° protractor. It is available from Nasco.

(However, most can be done on traditional 11 by 11 geoboards, or traditional circle geoboards.)

11 by 11 Geoboard

Geometry Labs (free download)

Area: Labs 8.4-8.6, 9.5
Distance: Labs 9.2, 9.4, 9.6
Similarity, Slope: Labs 10.1, 10.2

Algebra: Themes, Tools, Concepts (free download)

(Some of these lessons overlap and complement the ones in Geometry Labs)
Area: Lessons 1.12, 2.12, 4.12, 6.12, 11.A
Distance, Square Roots Lessons 6.12, 7.12, 9.1-9.4, 9.A, 9.9, 9.C,
Similarity, Slope: Lessons 3.12, 8.3, 11.3

Blog posts

Geoboards and Dot Paper
Geoboard Triangles
Inscribing Geoboard Squares in Polyominoes
No Three on a Line
Heilbronn's Triangle
Ariadne's String

On this sitefavicon

A debate about the geoboard
Proving Pick's Formula
Dot Papers
Connecting the Dots! (presentation slides): html | PDF | Keynote

Elsewhere

Virtual Geoboard (on the NRICH site in the UK)

Circle Geoboard

Geometry Labs (free download)

Angles: Labs 1.7-1.9
Symmetry: Lab 5.5
Area: Labs 9.5, 11.7
Basic trig: Labs 11.1-11.7
(All but the trig activities can be done on any circle geoboard. The trig activities require the CircleTrig geoboard.)

On this sitefavicon

(excerpts from Geometry Labs)
Angles
The 10cm Circle
10-cm circle paper
Top