I will use 479 - 156 as the example.
You can start off by breaking apart each number. The organizational tip I have is to line up the place values when you break apart the number. This way the numbers are not squished together.
Then the students know to circle their final answers.
Here is a LearnZillion video that shows how to subtract 3-digit numbers without regrouping using the break apart strategy. This video also calls it expanded form.
If you just want the LearnZillion quick code:
LZ3002
As always...
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