Mathematics · Grade 1 · Number Sense and Quantity · Term 1

Skip Counting by 2s, 5s, and 10s

Exploring skip counting by 2s, 5s, and 10s to understand the structure of the hundred chart and number patterns.

• Ontario Curriculum Expectations
• 1.NBT.A.1
• 1.OA.C.5

About This Topic

Skip counting by 2s, 5s, and 10s builds Grade 1 students' number sense by revealing patterns on the hundred chart. Students explore how counting by 10s traces horizontal rows, by 5s forms vertical columns, and by 2s creates diagonals. These patterns help answer key questions, such as predicting the next number after 35 when counting by 5s or justifying why grouping beats counting by ones for larger totals.

In the Number Sense and Quantity unit, this topic connects skip counting to everyday items like shoes in pairs or coins in nickels and dimes. Students develop skills in recognizing repeating sequences up to 100 and beyond, which supports addition strategies and place value foundations. Collaborative chart work encourages justification of observations, like why 10s align neatly across rows.

Active learning benefits this topic greatly. When students hop along floor number lines, fill charts with counters, or chant sequences while clapping, patterns become visible and kinesthetic. These approaches make counting joyful, address errors through peer talk, and solidify predictions in ways worksheets cannot.

Key Questions

1. Analyze what patterns you notice on a hundred chart when we count by tens.
2. Justify when it is more efficient to count by a group rather than by ones.
3. Predict what the next number will be if you are skip counting by 5s and the last number was 35.

Learning Objectives

• Identify the pattern when skip counting by 2s, 5s, and 10s up to 100.
• Demonstrate skip counting by 2s, 5s, and 10s using a hundred chart.
• Explain the relationship between skip counting by 10s and the rows on a hundred chart.
• Justify why skip counting is more efficient than counting by ones for specific numbers.
• Predict the next number in a sequence when skip counting by 2s, 5s, or 10s.

Before You Start

Counting by Ones to 100

Why: Students need a solid foundation in counting individual numbers before they can effectively skip count.

Number Recognition to 100

Why: Students must be able to recognize and read numbers up to 100 to participate in skip counting activities on a hundred chart.

Key Vocabulary

Skip Counting	Counting forward by a specific number, such as 2, 5, or 10, instead of counting by ones. This helps in identifying number patterns.
Pattern	A repeating or predictable sequence of numbers or shapes. Skip counting by 2s, 5s, and 10s reveals distinct number patterns.
Hundred Chart	A chart displaying numbers from 1 to 100 in a grid. It is a useful tool for visualizing skip counting patterns.
Sequence	A set of numbers that follow a specific order or rule. Skip counting creates number sequences.

Watch Out for These Misconceptions

Common Misconception

Skip counting by 5s always lands on numbers ending in 5.

What to Teach Instead

The sequence alternates between endings in 0 and 5, like 5, 10, 15, 20. Filling a hundred chart with markers shows this repeat clearly. Group discussions during chart work help students trace lines and correct their counts together.

Common Misconception

You can only skip count forward, not backward.

What to Teach Instead

Patterns reverse smoothly, such as 50, 45, 40 by 5s. Hands-on number line hops forward and back build flexibility. Peer challenges in pairs reveal how landmarks like multiples of 10 anchor both directions.

Common Misconception

Skip counting skips numbers entirely, so they do not count.

What to Teach Instead

All numbers remain part of the total; grouping just speeds recitation. Manipulating counters in groups of 2s or 5s shows the full quantity. Collaborative sorts reinforce that efficiency covers the same amount as ones.

Active Learning Ideas

Hundred Chart Hop: Small Groups

Draw a large hundred chart on the floor with tape. Groups take turns hopping by 2s, 5s, or 10s from start, naming numbers aloud. After each path, discuss the pattern traced. Switch sequences for next group.

30 min·Small Groups

Coin Skip Count Sort: Pairs

Provide pairs with play coins (nickels, dimes). Partners sort and count by 5s or 10s into piles, recording totals on charts. Compare piles and predict adding one more coin. Share efficient strategies with class.

25 min·Pairs

Chant and Clap Patterns: Whole Class

Students stand in a circle. Teacher leads chant by 2s with claps on evens, then 5s with jumps, and 10s with snaps. Pause for predictions on next numbers. Record class predictions on board.

20 min·Whole Class

Bead String Sequences: Individual

Give each student pipe cleaners and beads. String beads in groups of 2, 5, or 10, counting aloud as they add. Label ends with starting and ending numbers, then trade to extend patterns.

15 min·Individual

Real-World Connections

• Cashiers use skip counting to quickly count money, especially when dealing with multiple nickels (counting by 5s) or dimes (counting by 10s) to make change.
• Athletes often use skip counting for drills, such as doing 10 jumping jacks, then 10 more, and repeating 5 times to reach a total of 50 repetitions.

Assessment Ideas

Exit Ticket

Give students a hundred chart with some numbers missing. Ask them to fill in the missing numbers by skip counting by 5s. Then, ask: 'What do you notice about the numbers you filled in?'

Discussion Prompt

Pose the question: 'Imagine you have 30 shoes. How would you count them using skip counting? Which number would you skip count by and why?' Listen for students' reasoning about using 2s.

Quick Check

Call out a starting number and a skip counting number (e.g., 'Start at 20, skip count by 10'). Have students write the next three numbers in the sequence on a mini-whiteboard. Review responses to gauge understanding.

Frequently Asked Questions

What patterns show up on a hundred chart with skip counting by 10s?

Counting by 10s traces straight horizontal rows across the chart, from 1-10, 11-20, up to 91-100. Students see how each row starts with 1 in the ones place and adds a ten. Chart activities help them predict extensions beyond 100 and connect to place value shifts.

How to teach predicting next numbers in skip counting sequences?

Use visual aids like hundred charts or number lines marked with colors for each skip. Pause chants at points like after 35 by 5s and ask for group predictions. Follow with reveals and discussions on why the pattern repeats, building confidence in forwards and backwards counts.

Why is skip counting by 2s, 5s, 10s key for grade 1 number sense?

It shifts students from rote one-by-one counting to efficient grouping, revealing structure in numbers up to 120. Links to real contexts like money and pairs prepare for multiplication. Mastery here boosts addition fluency and pattern recognition across math strands.

How can active learning help grade 1 students master skip counting?

Active methods like floor hops, bead strings, and coin sorts make patterns physical and multisensory. Students internalize sequences through movement and touch, far beyond paper drills. Group rotations allow real-time feedback, peer teaching corrects errors fast, and joy from chants boosts engagement and memory.