Addition - Block Model Practice for Grade 3

Block models make the invisible structure of our number system visible. Third graders are transitioning from counting by ones to understanding place value (tens and ones). When they see blocks grouped in tens, they begin to understand why 23 + 14 is not just 'add the 2 and 1, then the 3 and 4'—they see that we're combining 2 tens with 1 ten and 3 ones with 4 ones. This visual anchor helps prevent errors and builds the foundation for multi-digit addition throughout elementary school.

This is called 'regrouping' or 'exchanging,' and it's a key concept in addition. Practice this specific skill in isolation first. Use physical blocks (or draw them) and show how 10 ones can be exchanged for 1 ten. Start with problems where regrouping is obvious, like 7 + 5. Let your child physically move 10 ones into a tens block, saying 'I can trade 10 ones for 1 ten.' Once comfortable, return to worksheet problems that require regrouping and reference this trading process.

Block models and fact fluency work together at this level. The models provide understanding of *why* facts work. However, third grade is also when students develop fluency with single-digit facts (like 7 + 5 = 12) through repeated practice. Use block models to explain why facts are true, but also allocate separate time for fluency practice. Once students understand the concept through models, they'll build speed through practice and games.

If your child demonstrates mastery, challenge them to solve problems without looking at the blocks first. Have them predict the answer using mental math, then check their prediction using the block model. You can also extend to three-addend problems (three block groups to combine) or ask them to create their own addition problems and represent them with drawn or physical blocks. Another option is to increase the difficulty by moving toward addition with numbers requiring more regrouping or larger numbers within the 100 range.