Engineering 'aha' Moments in Number

Calculating Changes is professional learning network grounded in the classroom. Teachers supporting teachers to build a firmly founded, creative number sense through Infant years, then extending it across the primary years. The network has built a rich resource of ideas, activities and approaches, accessible through this site, within the context of all children learning to work like a mathematician in best practice classrooms.

From February 2025, access to the Members section is no longer password protected. Access is free. The name of the section remains the same throughout because, through almost 30 years, Members created, shared and built together the brilliant learning experiences you will find here. Poly Plug, calculators and the concept of Threading are essential to success with these activities. These Members have proven that children can develop a number sense beyond what is normally expected for their age, and have documented a core curriculum for achieving that in Working Mathematically with Infants.

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All the ingredients. Poly Plug, calculators, kids & a reason for mathematical conversation.

Working Mathematically with Infants We are very happy with our WMI kit. We are problem solving and polyplugging away and having a great time. ... Kerry Lee, Buninyong Primary School Read more testimony in the Stories link. 45 Threaded Activities and 48 Investigations for Years K - 2 10 weeks of number work detailed in 6 scope and sequence planners - one planner per semester in each year Planners are flexible - you map the weeks into your yearly program Weeks build on weeks, years build on years Planners are designed to support group work/ work stations/ learning centres and whole class investigations You will need at least one class set of Poly Plug (25 in most schools), a class set of four function calculators and the free WMI manual See Materials above to read more about Poly Plug and Calculators Integrates with Maths With Attitude in Year 3 and beyond to continue a curriculum centred on learning to work like a mathematician Use this Order Form for Poly Plug and to receive the all the Free Mathematics Centre resource, which include WMI and MWA. Read about the great learning with WMI at Boroondara Park Primary School.

Explore WMI Manual Part A for further background and Sample Planner

Professional Development

WMI has been constructed to support in-house professional development. See Mathematics Centre Professional Development for further support for DIY professional learning, in particular, as a starting point, the workshop video titled Engineering 'aha' Moments in Number.