Partition the second number to subtract 10s then 1s

The ArithmeKit 214 activity is designed to teach children the concept of partitioning numbers to simplify subtraction. It involves breaking down the second number in a subtraction problem into tens and ones, and then subtracting them sequentially from the first number. This method helps students to understand the value of each digit and to perform subtraction more efficiently. For example, to solve 34 - 12, one would first subtract the ten (34 - 10) and then the two ones, resulting in a step-by-step calculation that is easier to comprehend. The activity provides a series of subtraction problems, such as 34 - 15, 24 - 13, and 43 - 14, where students are encouraged to apply this partitioning strategy.

Additionally, the ArithmeKit includes exercises that encourage students to create their own matching pairs problems and to fill in missing numbers in a series of calculations. This helps to reinforce their understanding of the relationship between subtraction and partitioning. For instance, students are asked to complete problems like 34 - 13 = 34 - 10 - __, where they must determine the missing number that represents the ones they need to subtract. The activity also prompts students to reflect on patterns they notice and to write out the calculations for various subtraction problems, further solidifying their grasp of the concept. By partitioning numbers into tens and ones, students can approach subtraction with greater confidence and accuracy.