Counting in 9s - PowerPoint

In a Year 4 mathematics lesson, students are introduced to the concept of counting in 9s, aiming to confidently count up to 108 in increments of nine. The lesson begins with an exploration of what it means to count in 9s, which simply involves adding 9 to the previous number in the sequence. For example, starting from 0, the sequence would be 9, 18, 27, and so forth. A practical tip is shared to make this process easier: when counting in 9s, one can add 10 to the previous number and then subtract 1 to arrive at the next number in the sequence. This technique highlights a pattern where, as the sequence progresses, the tens digit increases by one while the units digit decreases by one.

As students practice counting together, they are encouraged to observe the pattern in the numbers, especially the change in the tens and units as they count up to 90. To reinforce learning and make the activity more engaging, a "Top Tip" is provided that suggests a simple arithmetic trick to facilitate counting in 9s. Additionally, the lesson incorporates a timed challenge where students must quickly identify the missing number in a sequence, enhancing their speed and proficiency in counting by nines. For a more interactive experience, a maze worksheet is available where students count in 9s to help a pirate find treasure, allowing them to colour the correct path based on the counting sequence, with the option to move diagonally through the maze.