Education Technology

Year 10: Consul Monkey

by Texas Instruments


  • ACMMG243 Formulate proofs involving congruent triangles and angle properties
  • ACMMG244 Apply logical reasoning, including the use of congruence and similarity, to proofs and numerical exercises involving plane shapes


  • Similar Triangles
  • Congruent Triangles
  • Proof
  • Gradient
  • Linear

About the Lesson

Consul the Educated Monkey was a toy built in 1916. The toy consisted of a series of mechanical linkages, relying on geometric properties to generate multiplication tables. In this activity students use a dynamic, virtual representation of the toy to explore these geometric properties and how they were used to construct multiplication tables. Students are also invited to consider other applications of this wonderful toy. The activity involves proof by similarity and congruence, including angle properties and is scaffolded via questions and interactive content.