2nd Grade Add and Subtract within 100 Games and Practice

Practice Goals

• Understand adding and subtracting two-digit numbers with place-value strategies.
• Use open number lines, tens-and-ones blocks, and decomposed equations before switching to symbolic notation.
• Explain the answer in words, diagrams, or equations instead of guessing.

Common Mistakes

• Mixing tens and ones or applying regrouping steps without tracking value.
• Skipping the visual model and trying to memorize a procedure for add and subtract within 100.
• Finishing a mission without checking whether the answer matches the original story or unit.

Use Cases