Education Technology

Year 7: Factors that Count

by Peter Fox


ACMNA149 - Investigate index notation and represent whole numbers as products of powers of prime numbers


  • Prime,
  • Composite,
  • Factors,
  • Index
  • Exponent
  • Base

About the Lesson

Students use factor trees to determine the prime factorisation of a number and write the result as a product of its prime factors. Students physically manipulate the prime factors to successively produce and record all the factors helping them build an understanding of factor pairs and the general composition of a number and its factors.  Using an inquiry based approach, students explore the relationship between the prime factorisation and the quantity of factors.


Students can use a factor counting program to predict, validate or explore the quantity of factors for any number.  The Counting Factors activity provides a set of step by step instructions and questions so that students can independently write this program.