Decimal arithmetic are tools that assist in teaching decimal number operations, commonly including counting sticks, digit boards, and operation cards. Counting sticks are bundled in bundles of 10, which intuitively reflects the concept of "ten in ten"; The digital board is divided into individual and ten digit areas, where digital cards can be placed to understand the meaning of numbers; The calculation card contains addition, subtraction, multiplication, and division equations for practicing calculation rules. In teaching, be able to demonstrate the composition and operation process of numbers, and organize group counting competitions. Helping students master the principles of decimal system and enhance their computational abilities is a practical tool for teaching basic mathematics in primary and secondary schools.