Learning goals: Teacher Facing Comprehend the term “constraint” to mean a limitation on the possible or reasonable values a quantity could have. Use variables and the symbols =, $\lt$, and $\gt$ to represent simple constraints in a situation. Write expressions with numbers and letters to represent the quantities in a situation. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from Alg1.2 Linear Equations, Inequalities, and Systems, Algebra 1.