What is an effective way to scaffold place value and number sense for 4th- or 5th-grade learners?

• A. Use base-10 manipulatives to model digits and place value.
• B. Rely exclusively on mental math strategies without any concrete models.
• C. Teach place value by memorizing the number names only.
• D. Avoid discussing digit relationships and skip connections to money or measurement.

Answer: (A)

Understanding place value and building number sense is best supported with concrete, visual models that show how digits in different positions represent different magnitudes. Using base-10 manipulatives lets students physically build numbers with ones, tens, and hundreds (and even thousands) to see how a digit’s place changes its value. This tangible approach helps learners notice patterns, like why regrouping works in addition and subtraction, and why 3 in the hundreds place means 300, not 3. For 4th- or 5th-grade students, this solid connection between digits and their values makes the abstract idea of place value concrete, which strengthens overall number sense and supports later work with decimals and more complex math.

It also helps link place value to real-world contexts such as money or measurement, where the base-10 structure is evident and meaningful. By contrast, relying solely on mental math abstracts place value away from its magnitude, memorizing number names without understanding how digits relate across places, and skipping connections to digit relationships or real-world contexts misses essential supports students need to reason about numbers.