Exploring Numbers 11-20

Overview

Unit: Counting Adventures Ahead
Lesson: 2 of 25
Duration: 45 minutes
Class size: 25 students
Age group: Year 1 (5-6 years old)
National Curriculum Focus:

• Number – number and place value (Y1)
• Objectives:
  • Count to and across 100, forwards and backwards, beginning with 0 or 1, or from any given number (NC Reference: Number; Number and place value: Years 1)
  • Read and write numbers from 1 to 20 in numerals and words (NC Reference: Number; Number and place value: Years 1)

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Learning Objectives

By the end of this lesson, pupils will:

• Count confidently and fluently from 11 to 20 aloud and in sequence.
• Recognise and write numbers 11 to 20 in numerals.
• Read and write number words from eleven to twenty.
• Understand the place value concept of ‘tens and ones’ within these numbers.
• Make connections between counting objects and the corresponding numeral and word.

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Resources

• Number flashcards (11-20) with numerals and corresponding words.
• Whiteboards and pens for each pupil.
• Counting cubes or small counters (e.g., plastic bears).
• Large number line (0 to 20) displayed in classroom.
• Worksheets with tracing and matching exercises for numbers 11-20.
• ‘Tens and ones’ place value mats for pair work.
• Interactive number song focusing on 11-20 (audio or video).

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Lesson Structure

1. Starter (5 minutes): Counting Warm-up

• Begin by revisiting numbers 1-10 as a class, using a large number line.
• Ask pupils to count forwards from 1 to 10 with the teacher’s guidance.
• Quickly transition to counting from 11 to 20, encouraging pupils to suggest what comes next on the number line.
• Use flashcards to display numerals 11-20 and say each number aloud chorally.

2. Main Activities (30 minutes)

a. Number Recognition and Reading (10 minutes)

• Introduce the numerals 11-20 using flashcards. Show numeral on one side, then flip to show the number word on the other side. Pronounce each number word clearly and ask students to repeat.
• Play the number song that includes chanting and movement – encourage pupils to stand and clap as they say the numbers aloud.
• Pupils work in pairs with ‘tens and ones’ mats: teacher provides 1 ‘ten stick’ (bundle of 10 cubes) with 1 to 9 single cubes to model how numbers 11-20 are made. Pairs discuss how many tens and ones each number has.

b. Writing Practice (10 minutes)

• Distribute whiteboards and pens.
• Model writing numerals 11 to 20, emphasising formation and direction.
• Pupils trace these on worksheets, which include dotted numeral outlines and corresponding words below.
• Teacher moves around, providing guided support and verbal prompts (“Remember the one and then what comes next?”)
• Extension for fast finishers: write a number sentence like “11 is ten and one more”.

c. Counting Objects and Matching (10 minutes)

• Provide each pupil with a handful of counters or cubes.
• Call out a number 11-20 and ask pupils to count out that many counters carefully.
• Pupils then show their counters and match to the correct numeral and word flashcard laid out on their desks.
• Encourage them to say in full sentences: “I have 14 counters. Fourteen is ten and four more.”
• Teacher can invite a few pupils to come to the front and demonstrate.

3. Plenary (5 minutes): Reflect and Recall

• Gather pupils on the carpet. Play a quick “Number Detective” game:
  • Teacher says a clue, e.g., “I am between 12 and 14,” or “I have one ten and five ones.”
  • Pupils guess the number and show fingers or write it on mini whiteboards.
• Recap the names and shapes of numbers 11-20 both aloud and by pointing to the number line.
• Praise effort and encourage the phrase: “Counting Adventures help me explore numbers!”

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Assessment for Learning

• Observe pupils’ confidence and accuracy during counting and matching activities.
• Check pupils’ writing on whiteboards and worksheets for correct numeral formation and correct spelling of number words.
• Use questioning during ‘tens and ones’ activities to assess understanding of place value.
• Plenary answers to verify recall and ability to apply knowledge in clues.

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Differentiation

• For pupils needing additional support:

  • Provide extra manipulatives for hands-on counting.
  • Use tracing numbers with finger on sand tray or tactile number cards.
  • Pair with a peer buddy for guidance in writing and counting.

• For pupils who are ready to extend learning:

  • Challenge to write simple number sentences for two numbers (e.g., 16 = 10 + 6).
  • Introduce counting backwards from 20 to 11.
  • Suggest creating their own number flashcards including words and numerals.

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Links to Future Learning

• Foundation for using place value in addition and subtraction (Y1 Number: Addition and subtraction).
• Prep for exploring numbers beyond 20 and introduction to teens concept.
• Supports fluency in reading and writing numbers that they will apply in measurement, money, and data handling units.

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This detailed, hands-on lesson expands pupils’ understanding of numbers 11-20 with multisensory learning opportunities, ensuring the lesson is engaging, accessible, and fully aligned to the National Curriculum expectations for Year 1 mathematics.