This paper introduces tools for converting circular-featured-waste into polygonal construction parts and then 3D polyhedra. The tools, including diagrams, 3D printable joiners and mathematical formulae are designed for mathematics-related play, re-use, learning, design and improvisation. Activities for students include making assemblies, gathering…

This article is the third in a series of activities that discusses some interesting relationships with triangles. The first article (EJ1259412) introduced the various circles and centres involved with a triangle, as well as the Euler Line (named after the famous mathematician Leonhard Euler) which passes through four of the five centres. The…

This article is the fourth in a series of activities that discusses some interesting relationships with triangles. Brian Sherman shows an activity demonstrating Euler's Theorem, which gives the distance from between the circumcentre and the incentre of a triangle.

This article is the second in a series of activities that discusses some interesting relationships with triangles. Brian Sherman shows how to determine the altitudes of a triangle, its area, and the lengths of its circumradius and inradius. [For the first activity in the series, see EJ1259412.]

Tangrams are a traditional Chinese puzzle comprising seven pieces that fit together to make a square. The seven pieces include two large right angled isosceles triangles, one medium size right angled isosceles triangle, two small right angled isosceles triangles, a small parallelogram, and a small square. The literature shows tangrams have been…

Two examples of mathematical modelling are explored. Firstly, optimising the distance travelled when jumping from a swing is discussed. The second concerns optimising the distance travelled by monkeys when swinging from branch to branch.

Effective teaching requires enjoyable classroom tasks aimed at promoting students' learning of mathematics meaningfully, and previous research has demonstrated that the use of origami activities in mathematics classrooms can help achieve that goal. In this article, the authors describe their "LOVE MATH" one-straight-cut letter origami…

This article focuses on the experience of viewing polyhedra in modified kaleidoscopes, highlighting the perceptive acts that take place. It presents aspects of geometry, such as concepts and ideas involved in the visualization of polyhedra in kaleidoscopes, through an analyticalmathematical study of the reflection of images in mirrors and…

This article is the first in a series of activities that discusses some interesting relationships with triangles. Brian Sherman shows how to find five centres for a triangle--the circumcentre, the incentre, the orthocentre, the centroid and the nine-point centre, with four of the five to be found on the Euler line. With these centres, he shows…

The Modelling Dance task is a mathematical modelling task that explores the relationship between mathematics and dance. The authors share the task sequence, adaptations made to support virtual implementation, and evidence of student learning related to learning goals.

This practitioner article describes a lesson carried out in a high school classroom at the conclusion of a unit on exponential growth. Two teachers use a series of music-related activities to engage students in using and connecting multiple representations of exponential growth while exploring musical frequencies on a piano.

Area models are an important strategy for representing and solving multiplication problems under the Common Core State Standards for Mathematics (NGA Center and CCSSO 2010). The hands-on task presented in this article, featuring differentiation and open-ended learning, sets up students to discover area models for themselves. Organized around…

This article highlights the importance of re-defining units unconventionally with fractions. We provide three examples of tasks Grade 5 students engaged in; we highlight the creative ways that they flexibly re-defined units and engaged deeply with fractions. We offer suggestions for supporting unconventional units for promoting conceptual…

The purpose of this article is to report how Year 6 teachers used geometric reasoning tasks to foster students' mathematical attitudes and dispositions by encouraging communication as students constructed mathematical meaning for themselves. The Year 6 teachers implemented two tasks to provide a rich mathematical assessment opportunity…

We present an investigative activity that was set as part of a course of pre-service teachers of mathematics. The emphasis in the course was set on the importance of using the computerized technological tool for teaching the subject. The activity focused on investigating interesting geometrical conservation properties which are not known to the…