This add thousandths less than 10 without regrouping worksheet has a set of problems curated to ensure that your child becomes more proficient in addition. Students align the decimal points and use zeros as space holders as they add decimals in this worksheet. However, regrouping of numbers is not required here. This worksheet is about practicing with the horizontal format in which numbers are written side by side. To develop flexibility with numbers and operations, students need to have enough practice in this format and not just rely on the vertical/column method.