Year 2 Place Value: Partition, Regroup and Rename Numbers

Place value tells us what each digit is worth because of its position. Students connect written digits to grouped materials, partition numbers into hundreds, tens and ones, and then rename the same number using different groupings without changing its value.

• Read a two- or three-digit number and explain the value of each digit.
• Partition a number in standard form, such as 245 = 200 + 40 + 5.
• Regroup one hundred as 10 tens and one ten as 10 ones.
• Rename a number in equivalent ways, such as 245 = 24 tens + 5 ones.
• Explain the role of zero as a placeholder, for example in 305 or 420.

A number can be represented in several equivalent ways. Regrouping changes how the quantity is organised, not how much there is.

Each representation has the same total value: 245.

1. Build the number. Use base-ten blocks, bundled sticks or grouped counters to show hundreds, tens and ones.
2. Match materials to digits. For 352, connect 3 hundreds, 5 tens and 2 ones to the digits 3, 5 and 2.
3. Partition. Write 352 as 300 + 50 + 2.
4. Regroup. Trade one hundred for 10 tens, or one ten for 10 ones, while checking that the total stays the same.
5. Rename. Express the number in a new equivalent form and explain why it is still the same number.
6. Use zero deliberately. Compare numbers such as 305, 350 and 530 so students explain what each zero means.

Partition 384

384 has 3 hundreds, 8 tens and 4 ones, so 384 = 300 + 80 + 4.

Rename 384 using tens and ones

3 hundreds can be regrouped as 30 tens. Then 30 tens + 8 tens = 38 tens, so 384 = 38 tens + 4 ones.

Rename 62 for calculation

62 can be written as 6 tens + 2 ones or as 5 tens + 12 ones. The grouping changes, but both representations equal 62.

Explain the zero in 407

407 has 4 hundreds, 0 tens and 7 ones. The zero keeps the hundreds and ones in their correct place-value positions.

Key idea: A number can be partitioned in standard and non-standard ways. Regrouping changes the parts but not the total value.

Remember

• Partition three-digit numbers
• Regroup tens and ones
• Use non-standard groupings
• Explain zero
• Keep value after renaming

Quick questions

• Rename 246 in two ways.
• What does the 0 mean in 509?
• Is 300 + 40 + 12 equal to 352? Explain.
• Write 470 as hundreds, tens and ones.

If an answer is uncertain, return to the model and explain what each part represents before calculating or drawing a conclusion.

• Reading digits instead of values: in 352, the 5 represents 5 tens or 50, not simply 5.
• Changing the total while regrouping: require students to prove that the old and new representations are equal.
• Thinking there is only one correct partition: show several valid representations of the same number.
• Ignoring zero: compare 305 and 35 to show why zero matters in positional notation.
• Writing 24 tens as 24: connect the language “24 tens” to its value of 240 before adding the ones.

• Support: keep base-ten materials visible and use place-value mats labelled hundreds, tens and ones.
• Core: move between materials, numerals, expanded notation and renamed forms.
• Extension: challenge students to find three or more different equivalent regroupings and justify each one.

Content description: partition, rearrange, regroup and rename two- and three-digit numbers using standard and non-standard groupings; recognise the role of a zero digit in place value notation.

• E1: compare the digits of a number with materials grouped into hundreds, tens and ones, and explain the meaning of each digit in the materials.
• E2: rename numbers in different ways using place-value knowledge; for example, rename 245 as 24 tens and 5 ones or as 2 hundreds and 45 ones.

1. Partition 326 into hundreds, tens and ones.
2. Write 326 in expanded notation.
3. Rename 326 using tens and ones only.
4. Explain why 5 tens + 12 ones is still 62.
5. What does the zero mean in 408?
6. Is 2 hundreds + 15 tens + 6 ones equal to 356? Explain.

Use the topic guide for planning, present the static Teacher Slides for explicit instruction, then choose the worksheet, supported Practice or independent Test. If a student can perform a regrouping but cannot explain why the value is unchanged, return to physical materials and equivalent trades.

Curriculum equivalents for Partition, rearrange, regroup and rename two- and three-digit numbers using...

Mapped skill: partition, rearrange, regroup and rename two- and three-digit numbers using standard and non-standard groupings; recognise the role of a zero digit in place value notation

These references identify matching or closely related learning. Curriculum sequence, terminology and depth vary, so teachers should use the mapped skill and lesson difficulty to confirm suitability.

Australian Curriculum v9.0 is the canonical source for this SkillrHub lesson. Victoria and NSW entries name the closest published state codes or outcomes; international entries are planning references rather than claims of identical curricula.

• Australian Curriculum Version 9.0
• Victorian Curriculum F–10
• NSW Curriculum

• AC9M2N01: Numbers to at least 1000
• AC9M2N03: Halves, quarters and eighths
• AC9M2N04: Addition and subtraction strategies
• AC9M2N05: Equal groups, arrays, multiplication and division