Mathematics at SBS emphasizes in-depth mathematical thinking, rather than superficial exposure to disconnected concepts. Students at all grade levels spend time using manipulatives and exploring mathematics concepts in real-life settings. They are encouraged to find multiple solutions to the problems they work on, and to express their thinking through drawings, writings, and discussions.

The students are challenged to invent their own strategies and procedures for problem solving before learning the traditional algorithms, and work cooperatively in small groups, with partners, and individually. Qualitative assessment of students's problem solving abilities guides instructions. Math units and curriculum materials are drawn from a variety of sources including Marylyn Burns, T.E.R.C Investigations, and Addison Wesley.