Counting on is a simple addition strategy that helps young learners add without starting at 1 every time. Instead of counting both groups from the beginning, students hold one number in their mind and count forward by the other number. This is faster, easier, and builds confidence with number order.
A number line from 0 to 20 is a helpful tool because children can see each jump clearly.
Key Facts
- To count on, start with one addend and count forward by the other addend.
- It is usually easier to start with the bigger number.
- 8 + 3 means start at 8 and count 3 more: 9, 10, 11.
- 8 + 3 = 11.
- Each finger or number line jump counts as 1 more.
- Addition can be written as a + b = sum.
Vocabulary
- Add
- To add means to put numbers or groups together to find how many there are in all.
- Addend
- An addend is a number that is added to another number.
- Sum
- The sum is the answer to an addition problem.
- Counting on
- Counting on is an addition strategy where you start at one number and count forward.
- Number line
- A number line is a line with numbers in order that helps show counting and adding.
Common Mistakes to Avoid
- Starting over at 1, which makes the problem take longer and can lead to losing count. For 8 + 3, start at 8, not at 1.
- Counting the starting number as the first jump, which adds one too many. If you start at 8, the first count is 9.
- Using the smaller number as the start when the larger number is easier, which makes more counting work. For 3 + 8, start at 8 and count on 3.
- Making the wrong number of jumps on the number line, which changes the sum. For 8 + 3, make exactly 3 jumps.
Practice Questions
- 1 Use counting on to solve 9 + 4 = ?. Start at the bigger number and write the numbers you count.
- 2 Use a number line to solve 6 + 5 = ?. Circle the number you start on and show each jump.
- 3 Why is it helpful to start with the bigger number when using counting on?