Divide with remainders and confirm that every remainder is smaller than the divisor.
Not every division comes out even. Whatever is left over after making as many equal groups as possible is the remainder.
A remainder must always be smaller than the divisor. If it is not, that means at least one more full group actually fits, and the quotient needs to go up by one.
Mastery looks like: They divide with remainders accurately and check that every remainder is smaller than the divisor.
Common stumbles: Leaving a remainder that is equal to or larger than the divisor, a sign a bigger quotient digit was needed; forgetting to include the remainder in the final answer.
See it visually
Interactive, spoken-aloud tools that show this idea in motion.