In this lesson plan, your learner will practice adding across 10 by applying the make-ten strategy. This lesson focuses on adding two single-digit numbers that result in crossing over the ten boundary. By partitioning one of the addends, your learner will transform the problem into a simpler addition task.
Here are a few concepts that are helpful to know for this lesson:
Crossing the Ten Boundary: Adding two single-digit numbers where the sum exceeds ten. For example, 7 + 5 = 12 involves crossing the ten boundary.
Applying Make-Ten: Applying the make-ten strategy involves partitioning one addend into two parts so that one of the parts can pair with the other addend to make ten. For example, in 7 + 5, partition 5 into 3 and 2, so 7 + 3 = 10, then 10 + 2 = 12.
Teaching Plan
The following activities will help your learner become confident in using the make-ten strategy for solving addition problems that cross ten. Be sure to work at a pace that is comfortable for your learner.
Examples and visuals to support the lesson:
1. Introducing Crossing the Ten Boundary
Introduce the concept of crossing the ten boundary by using a story with a practical representation. For example, "A ride at the funfair has ten seats in each carriage. You have to fill up the whole carriage before children can get in a new one. There are seven children in the first carriage. Five more get on. How many children are there altogether?"
Note that by stating that a whole carriage has to be filled first, your learner will realize that 3 children will go in the first carriage and the other 2 children will go in the second carriage. This encourages them to partition 5 into 3 and 2.
Introduce the idea that an addition problem with two addends can be transformed into an addition problem with three addends by partitioning one of the addends into two parts. For example, when adding 7 + 5, five can be partitioned into 3 + 2, resulting in the expression 7 + 3 + 2.
Use tens frames to help your learner see the opportunity to make ten by combining 7 and 3. Then combine the 10 with 2 to find the total sum of 12.
Skill Check
I know that when I add numbers, I can split one of the numbers into two smaller parts.
2. Using the Part-Part-Whole Model
Use the part-part-whole (cherry) representation to help your learner move on to an equation representing the partitioning.
Encourage your learner to describe the steps in full sentences. For example: "First, I partition the five: three plus two is equal to five." "Then, seven plus three is equal to ten." "And ten plus two is equal to twelve."
Stay with the same example until your learner is confident with the process.
Introduce the generalized stem sentence to reinforce the strategy: "First, I partition the ___: ___ plus ___ is equal to ___." "Then, ___ plus ___ is equal to ten." "And ten plus ___ is equal to ___."
Skill Check
I can explain the steps for solving an addition problem that involves splitting a number into two parts.
3. Modeling with Ten-Frames and Number Lines
Provide several examples for your learner to explore in pairs using the tens frame. Encourage them to repeat the stem sentence as they move the counters around.
Ensure that your learner uses the tens frames to expose the mathematical structure, rather than using them to ‘count all’ or ‘count on’ without making ten.
Represent this strategy using a number line to visualize the addition process. For example: "Start at 7, then move 3 steps to reach 10, and finally move 2 more steps to reach 12."
Gradually build towards using just the symbolic notation. Begin with equations with terms on both sides to practice and embed the concept before moving to a less scaffolded approach. For example: "7 + 5 = (7 + 3) + 2 = 10 + 2 = 12."
Skill Check
I can use ten-frames, number lines, and equations to show an addition problem that involves splitting a number into two parts and crossing over ten.
4. Ongoing Practice
Provide regular practice to develop fluency. Some learners may need to use concrete resources for longer. Encourage them to visualize how to partition the addend and ‘make ten.’
For learners who grasp the strategy quickly, offer opportunities to find the answer in various ways. They may enjoy partitioning both addends into 5 + something. For example: "8 + 6 = (5 + 3) + (5 + 1) = 14" or "8 + 6 = (5 + 5) + (3 + 1) = 14"
Use a challenging task to promote deeper thinking. For example, start with a set of expressions, equations, and inequalities that have missing numbers. Give your learner a list of digits to fill in for the missing numbers, instructing them that each digit can only be used once.
Summary
By the end of this lesson, your learner will master adding across ten using the make-ten strategy. They will understand how to partition addends to simplify addition, making math both engaging and intuitive.
With over 12 years of experience as a classroom teacher, tutor, and homeschool parent, my specialty is easing math anxiety for students of all ages. I'm committed to empowering parents to confidently support their children in math!
Skill Check