High

Maps at four levels of scale—global, national, regional, and local—provide a context for mathematical investigations that help teachers learn about their students.

The minus sign is a mathematical symbol that is multi-functional. Yet, how often is its use explicit to the non-mathematician, or more importantly the learner, who is expected to interpret the symbolism appropriately, when often the "meaning" stems from context of its use. From the perspective of the learner, such nuances of use simply lead to confusion which has the potential for lifelong misconceptions within their personal mathematics. This commentary is based on working with children on their journey through mathematics, it provides insights into the complexity of mathematical communication for those "learning the language".