This activity is to practice simplifying expressions with variables with whole numbers. Students will apply substituting a value for a variable and using the order of operations to simplify each expression. The 16 expressions simplify to 35, 24, 51, or 15. Students simplify the expression and sort them on to the correct answer mat. This activity can be printed and laminated for repeated use or printed for each student. This activity is great for small group rotations, collaborative work, or independent work.