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I have watched my children progress in this area through the years. From shape sorting blocks, to wooden bricks to Duplo, Lego and games by THINK FUN and GAMEWRIGHT.
Formally, we worked through Singapore Maths Primary books. The scaffolding in the curriculum and problem solving type of questions exposed them to an array of perspectives in approaching a given problem.
I was delighted to find the following riddle to solve in
I think the creativity in the presentation of the problem to solve is engaging. The solution to the problem involves applying fundamental Mathematical principles. It gives a sense a greater purpose to learning these principles rather than knowing it as it might be asked in an exam.