Subtract 100 Worksheet for Class 2

A subtract 100 worksheet for Class 2 helps children see that taking one hundred from a three-digit number changes the hundreds place while the tens and ones stay the same in the examples shown. The activity includes 681 - 100, 560 - 100 and 390 - 100. Children choose or enter the difference and can check the result with place-value reasoning.

What changes when 100 is subtracted

One hundred is 1 hundred, 0 tens and 0 ones. When a number has at least one hundred available, subtracting 100 removes one hundred without changing the tens or ones. Thus 681 becomes 581: 6 hundreds becomes 5 hundreds, while 8 tens and 1 one remain.

Place-value change after subtracting 100

Starting number	Hundreds change	Tens and ones	Difference
681	6 to 5	81 stays 81	581
560	5 to 4	60 stays 60	460
390	3 to 2	90 stays 90	290

This is the central idea in subtract 100 from a three digit number practice.

Worked examples from this activity

681 minus 100

Write 681 as 6 hundreds, 8 tens and 1 one. Remove 1 hundred. Five hundreds, eight tens and one one remain, so 681 - 100 = 581. Among the visible choices, 581 preserves the final two digits and decreases the hundreds digit by one.

560 minus 100

Five hundreds become four hundreds. The 6 tens and 0 ones stay, producing 460. The zero in the ones place remains important even though it represents no individual ones.

390 minus 100

Three hundreds become two hundreds. Nine tens and zero ones do not change, so the difference is 290.

A place-value method for minus 100

Read the full three-digit number.
Identify the hundreds digit.
Check that the task says subtract 100, not subtract 10.
Decrease the hundreds digit by one.
Copy the tens and ones digits without changing their positions.
Read the new number and write the equation.

For 742 - 100, the hundreds digit changes from 7 to 6, while 42 remains. The difference is 642. This extra example follows the same principle but is separate from the verified questions on the page.

How to check each answer

Use the inverse operation: add 100 to the difference. If 581 + 100 returns 681, the subtraction is consistent. A child may also compare size. The answer should be exactly one hundred less, not ten less and not one less.

The tens digit should match the starting number.
The ones digit should match the starting number.
The hundreds digit should be one smaller.
The difference should be less than the original number.
Adding 100 should reconstruct the original number.

These checks catch transcription errors before a child moves to the next item.

Parent guidance with hundreds tens and ones

Build 681 with place-value cards or spoken parts: 600 + 80 + 1. Remove the 100 part from 600, leaving 500 + 80 + 1. Combine the parts again to make 581. Repeat with 560 and 390 so the child sees that tens and ones can include zero.

Ask, How many hundreds are there now?
Cover the hundreds digit and compare the final two digits.
Say both numbers aloud to reinforce their relationship.
Use one example with cards before returning to the digital question.
Let the child explain why no borrowing is needed in these examples.

Teacher prompts for Class 2

Display a three-column hundreds-tens-ones chart. Place the digits of 681 in their columns, then cross out one hundred and replace 6 with 5. Keep 8 and 1 visible. Ask learners what changed and what stayed constant.

Which place holds the 1 hundred we are removing?
Why does the tens digit remain 8?
How is subtracting 100 different from subtracting 10?
Can addition check this answer?
Which wrong choice changes the wrong place?

Invite children to justify one choice rather than completing many items silently. The explanation reveals whether they understand place value or are copying a visual pattern.

Common errors when subtracting 100

Changing the tens digit: that would match subtracting 10, not 100.
Changing every digit: only one hundred is removed in the displayed examples.
Dropping a zero: write 460, not 46, after 560 - 100.
Adding instead of subtracting: the difference must be smaller than the starting number.
Copying the original number: identify and change the hundreds digit deliberately.
Using a memorised rule without checking: add 100 back to confirm the result.

Practice ideas without changing the skill

Hundreds card exchange

Show six 100 cards, eight 10 cards and one 1 card. Remove a 100 card and name what remains.

Find the wrong answer

Compare 560 - 100 = 550 and 560 - 100 = 460. Ask which place each answer changed.

Missing starting number

Say, A number minus 100 is 290. Add 100 to find the starting number 390.

Number line jump

Mark 681 and make one backward jump of 100 to 581. Keep this as a place-value jump rather than counting back by ones.

Useful next steps include adding 100, counting in steps of 100, comparing three-digit numbers and subtracting other multiples of 100. Regrouping belongs to a different stage. The visible questions here can be solved by removing exactly one hundred while preserving tens and ones.