These 4th Grade Common Core Numbers and Operations in Base Ten leveled assessments cover all common core standards for 4NBT, including: patterns in place value, different number forms, rounding, addition, subtraction, and addition and subtraction word problems {4.NBT.1, 4.NBT.2, 4.NBT.3, 4.NBT.4, 4.OA.3}. Three versions of each number operations in base 10 assessment (labeled Version 1, Version 2, and Version 3) with three differentiated levels of mastery within each version (called "Building