Students represent one- and two-step whole-number situations with labeled drawings, equations, and unknowns, identify relevant or missing information, choose addition, subtraction, multiplication, or division, and solve problems involving addition and subtraction through 1,000 and multiplication and division within 100. They use inverse relationships to check calculations, estimate to assess reasonableness, find and correct errors, and compare strategies by explaining the role of place value and operation properties. Students explain solutions in words, create coherent word problems for equations, apply logical elimination to arithmetic and simple data or shape problems, and interpret remainders and intermediate results.