### Domain I: Number and Operations

 Rationale: Historically, number has been the cornerstone of the entire mathematics curriculum. All the mathematics proposed for prekindergarten through grade 12 is strongly grounded in number. The principles that govern equation solving in algebra are the same as the structural properties of systems of numbers. In geometry and measurement, attributes are described with numbers. The entire area of data analysis involves making sense of numbers. Through problem solving, students can explore and solidify their understandings of number.  Understanding number and operations, developing number sense, and gaining fluency in arithmetic computation form the core of mathematics education for the elementary grades. As they progress from prekindergarten through grade 12, students should attain a rich understanding of numbers—what they are; how they are represented with objects, numerals, or on number lines; how they are related to one another; how numbers are embedded in systems that have structures and properties; and how to use numbers and operations to solve problems. Modified from the National Council of Teachers of Mathematics Principles and Standards for School Mathematics (2001) Cluster areas included in the PPST: Mathematics under Domain 1: Numbers and Operations include concepts and procedures related to order, equivalence, place value, number properties, operation properites, computation, estimation, proportional reasoning, percents, and numerical reasoning. According to the PRAXIS II Study Guide, these content areas account for 33% of the mathematics component of the PPST. Next Topic >  Order