Begin with pairing numbers that add up to ten: Start by teaching children how to break down subtraction problems by using the sum of ten as a helper. For example, if a problem involves 13 – 7, guide them to think of it as 10 + 3, then subtract 7 from the 10. This simplifies the problem and speeds up mental calculations.
Use visual aids to reinforce the method: Draw or provide tools such as number lines or counters that show how breaking numbers into parts can help simplify subtraction. When learners see the steps broken down visually, it helps solidify the concept and makes it easier to apply independently.
Encourage practice with varied problems: Create multiple exercises that ask students to solve subtraction problems using the “make a ten” approach. Include a mix of numbers so they can practice this technique in different contexts, which will help improve both their subtraction speed and understanding.
Using the “Make a Ten” Strategy for Simple Subtraction
Start with problems that involve numbers close to ten: When dealing with subtraction problems, encourage students to identify numbers that can be combined to make ten. For example, in a problem like 12 – 8, break it down into 10 + 2, then subtract the 8 from the 10. This method reduces the complexity of the calculation.
Provide step-by-step examples: Offer clear, step-by-step examples that show how to break down subtraction problems into parts that make ten. For instance, 15 – 7 becomes 10 + 5, then subtract 7 from 10, making it easier to complete mentally.
Use a structured format to guide students: Use a table to visually guide students through the process. This helps them see the relationship between the numbers and apply the technique effectively. Here’s a simple table to illustrate this method:
| Problem | Step 1: Break into parts | Step 2: Subtract from 10 | Answer |
|---|---|---|---|
| 13 – 6 | 10 + 3 | 10 – 6 = 4 | 7 |
| 14 – 5 | 10 + 4 | 10 – 5 = 5 | 9 |
| 18 – 9 | 10 + 8 | 10 – 9 = 1 | 9 |
Practice with a variety of problems: To master this method, give students different subtraction problems that require breaking numbers into sums that make ten. The more practice they get, the faster and more confident they’ll become in solving similar problems.
How to Teach Subtraction Using the Make Ten Strategy
Introduce the concept with simple examples: Start by explaining how to break down larger numbers into smaller parts that add up to a round number. For example, in a problem like 14 – 6, teach students to think of it as 10 + 4, then subtract 6 from 10. This makes the math easier and faster.
Use visual aids: Draw number lines or use counters to help illustrate how breaking a number into a sum of parts works. Show how 13 – 5 becomes 10 + 3, and then subtract 5 from the 10. Visualizing this helps students grasp the idea and build confidence.
Practice with gradual difficulty: Begin with simple problems that involve smaller numbers, and gradually increase the complexity as students become more comfortable with the process. For example, start with 12 – 3, then move on to 15 – 8, and so on.
Encourage mental math: As students become more familiar with this approach, encourage them to perform these calculations in their heads. This strengthens their mental math skills and speeds up their ability to solve subtraction problems without relying on written methods.
Reinforce with repetition: Provide plenty of practice problems that follow this method. Repetition is key to helping students internalize the technique and apply it quickly when solving different subtraction tasks.
Step-by-Step Guide to Creating a Make Ten Subtraction Worksheet
1. Choose the range of numbers: Select numbers that are close to ten to practice the technique. Start with simpler problems, like numbers between 10 and 20, and gradually increase the complexity by including larger numbers. Aim to keep the problems within a manageable range.
2. Create problem sets with both single and multi-step solutions: Prepare problems where the numbers can easily be split into parts that add up to 10. For example, include exercises like 12 – 4, 15 – 7, and 19 – 8, which require breaking the numbers into tens and ones. Then include more challenging problems where this method can be applied in multiple steps.
3. Provide space for students to show their work: Leave enough space for students to write their intermediate steps. This helps them visualize the process of splitting the numbers and subtracting from the ten, reinforcing the technique and improving accuracy.
4. Include a section with number lines or visual aids: Some students benefit from visualizing the problem. Include number lines where students can mark the numbers and trace the steps as they subtract. This makes the abstract concept more concrete and easy to follow.
5. Add a variety of exercises: Mix problems of different formats. For instance, include both horizontal and vertical problems, and adjust the level of difficulty. Start with easy problems and gradually introduce more complex ones as students master the technique.
6. Provide a section for reflection: After each set of problems, include a small section where students can reflect on the method. Encourage them to describe how they broke the numbers into parts and how it helped them solve the problem. This reinforces the learning process.
7. Include a solution key: After completing the worksheet, provide a solution key with step-by-step explanations of how to break down and solve each problem. This helps students verify their answers and understand any mistakes they may have made.
Common Mistakes and Tips for Mastering the Make Ten Method
Mistake 1: Not recognizing when to break the number: Students sometimes fail to identify which number should be split into parts. A good practice is to focus on making the larger number break into a sum that includes 10. For example, in a problem like 14 – 6, students should first break 14 into 10 + 4 and then subtract 6 from 10.
Tip: Encourage students to always ask, “How can I split this number to make it easier to subtract?” This helps them focus on the right parts and avoid unnecessary complexity.
Mistake 2: Overcomplicating the problem: Students might try to break numbers into too many parts, making the process more difficult. For example, in 16 – 7, instead of breaking 16 into 10 + 6, students may attempt to split it further, leading to confusion.
Tip: Keep the breakdowns as simple as possible. If a number can be split into 10 and a smaller part, focus on that instead of complicating the process with more steps.
Mistake 3: Forgetting to adjust after making a ten: Some learners forget that after making the ten, they still need to subtract the smaller part from it. For example, in 13 – 5, students may subtract 10 from 13 and then forget to subtract the remaining 5, resulting in an incorrect answer.
Tip: Remind students to always check their work after they’ve made a ten. Revisit the remaining part of the equation to ensure accuracy in their final answer.
Mistake 4: Not practicing enough: Students may struggle with the technique if they don’t get enough practice. This method requires repetition to build confidence and mental agility.
Tip: Provide plenty of practice problems with varying levels of difficulty. Start with simple problems and gradually increase complexity to help students improve their skills and confidence.
Mistake 5: Misunderstanding the relationship between numbers: Some students might not grasp how splitting numbers into tens and ones helps with subtraction. They might view the process as too abstract.
Tip: Use concrete examples like number lines or counters. Visual aids make the concept more tangible and allow students to physically see the subtraction process, making it easier to understand and apply.