Assess students' ability to solve addition and subtraction word problems within 20 by modeling with manipulatives (counters/cubes), constructing number bonds, and applying counting-on/counting-back strategies. Include single-step and simple two-step items, missing-addend and comparison problems, and require students to show or explain their reasoning using drawings, number bonds, or physical manipulatives. Evaluate accuracy, choice of strategy, and explanation to inform instruction.