Subtraction is an essential mathematical skill that students should learn. However, not all students find it easy to master. This is especially true when they need to subtract numbers that involve regrouping or borrowing, as it requires more advanced computational skills.
One effective way to help students with subtraction is by employing the concept of compensation. Compensating a number means adjusting it by adding or subtracting another number to make the calculation more manageable. This concept gives students a more intuitive sense of how numbers and operations work, making subtraction easier to understand.
Here are some activities to teach students how to use compensation to subtract numbers up to two digits:
1. “Hop, Skip and Jump” Game
This game is a fun way for students to visualize subtraction using compensation. Begin by drawing a hopscotch board on the ground and write subtraction problems on each square. The students hop, skip, or jump on the designated square while reciting the problem out loud. For example, if the square says “15 – 7,” the student hops on the square and then jumps forward seven squares to the “8” square. They then recite the answer, which is 8.
Encourage students to use compensation when the problem involves subtracting two-digit numbers. For instance, when subtracting 24 – 16, they can add 4 to 16, making it 20. This way, they will only have to subtract 20 from 24, which is much easier than subtracting 16 from 24.
2. “Find the Treasure” Challenge
This activity involves putting the students into groups and giving them a series of subtraction problems. The students have to solve the problems to unlock clues that lead them to the treasure. For each problem, students should use compensation to simplify the calculation if necessary.
To make the activity more exciting, you can hide the clues around the classroom or school and create a map to help the students navigate. Additionally, you can increase the level of difficulty by incorporating two-digit numbers and increasing the number of problems.
3. “Calculator Challenge” Worksheet
Give the students a worksheet with subtraction problems that involve compensating. Encourage them to use a calculator to check their solutions. Use problems that require the student to subtract two-digit numbers and compensate using the tens place.
For example, give them the problem 67 – 38 and ask them to use compensation to solve the problem. They can add two to 38 to make it 40 and subtract 40 from 67, making the difference easier to obtain. This exercise helps the student practice compensation with real-life problems and gets them more comfortable using the technique.
Final thoughts
Using compensation in subtraction is a skill that students can use in many areas of life. By incorporating these activities into your lessons, you will help your students strengthen their mathematical abilities while also making learning fun and engaging. Be sure to congratulate them on their progress and praise them for employing compensation.
