3rd Grade Math Worksheets Online - SplashLearn Printable 3rd grade math worksheets aligned with Common Core Standards. Download Math Worksheets for 3rd Graders Today! ... Subtract Multiples of 100 from 3-Digit Numbers: Horizontal Subtraction. Assess your math skills by subtracting multiples of 100 from 3-digit numbers in this worksheet. 3. VIEW DETAILS. Subtraction With Regrouping