Counting Every Second

Overview

In this 30-minute lesson, students explore whether Tama has correctly converted seconds into minutes, then use the relationship between seconds and minutes to solve and explain time problems. The lesson builds on familiar clock and duration knowledge and connects digital notation, timelines and calculation.

Learning intentions

• WALT convert seconds into minutes when the number of seconds is a multiple of 60.
• WALT use the fact that 60 seconds equals 1 minute.
• WALT explain how a timeline or calculation helps us solve a time problem.
• WALT use time vocabulary accurately: seconds, minutes, hours, digital, analogue, 24 hours and timeline.

Success criteria

• I can recall that 60 seconds equals 1 minute.
• I can divide a number of seconds by 60 to find the number of minutes.
• I can show my thinking with a timeline, groups of 60 or a calculation.
• I can decide whether Tama’s answer is successful and explain why.

Curriculum links

• Measurement — measure and describe duration using appropriate time-based units, including seconds, minutes and hours.
• Measurement — use familiar benchmarks and calculations to estimate and measure duration.
• Mathematics and Statistics Mathsteasers — engage with higher-order thinking questions that deepen understanding.
• Mathematical practices — reason, communicate ideas, choose representations and justify a conclusion.

Lesson structure (30 minutes)

1. 0–4 min · Hook: Is Tama successful? Teacher displays the opening question from the introduction and Tama problem slides: “Tama says 120 seconds is 120 minutes. Is Tama successful?” Students think silently, show thumbs up/down/unsure, then explain their first idea to a partner.

2. 4–9 min · Connect to known facts. Teacher revisits an analogue clock, a digital clock and a 24-hour day using the time vocabulary and benchmark slides; emphasise that one minute contains 60 seconds and ask, “How many groups of 60 are in 120?” Students chorally read the key vocabulary, make two groups of 60 with counters or fingers, and state the matching equation: 120 seconds = 2 minutes.

3. 9–15 min · Model conversion. Teacher models the example on page 110: identify the unit, group the seconds into 60s, and record either a repeated subtraction, a timeline or division by 60. Show that 180 seconds is 3 minutes because 180 ÷ 60 = 3. Students help complete a second example and explain why dividing by 60 is appropriate. Address the misconception that the numeral stays the same when the unit changes.

4. 15–23 min · Guided textbook and workbook practice. Teacher directs pairs to complete selected questions from textbook pages 110–112, checking each answer by asking, “How many full groups of 60?” Students use the seconds-to-minutes practice sheet alongside workbook pages 75–76 to solve conversion questions, draw timelines where useful, and mark whether Tama’s statements are successful or unsuccessful. Teacher circulates, prioritising students who count inaccurately or confuse seconds and minutes.

5. 23–27 min · Explain and compare. Teacher selects two solutions, including a timeline and a division strategy, and displays the discussion prompts from the worked examples and discussion slides. Students compare the methods with a partner using the stem, “I know this is correct because…” and correct one deliberately incorrect conversion, such as 240 seconds = 240 minutes.

6. 27–30 min · Exit check and plenary. Teacher asks students to complete the final question on the reflection and exit section: “Convert 300 seconds into minutes. Show your thinking. Is the statement ‘90 seconds = 90 minutes’ successful? Explain.” Students submit their response and share one useful benchmark before packing away.

Resources

• the complete time conversion slide deck
• the seconds-to-minutes practice sheet
• Mathematics textbook, pages 110–112
• Mathematics workbook, pages 75–76
• Analogue clock or demonstration clock
• Digital clock display or projected digital time
• Small counters, linking cubes or bottle tops for groups of 60
• Whiteboards and pens
• Pencils and erasers

Assessment

• During the hook and modelling, listen for whether students know that 60 seconds makes 1 minute and can distinguish the units.
• While students work, check representations and questions: Can they make equal groups of 60, divide by 60, and explain their answer?
• Use the exit response to identify students who can convert accurately and justify whether a statement is successful. Revisit the relationship between seconds and minutes with students who need further support.

Differentiation

• Support students with a visible “60 seconds = 1 minute” reference, counters arranged in groups of 60, a pre-drawn timeline and the sentence frame, “___ seconds is ___ groups of 60, so it is ___ minutes.”
• Allow students to solve using repeated subtraction or grouping before introducing division notation. Pair students deliberately and read questions aloud where needed.
• For EAL learners, use gestures and visuals for seconds, minutes and groups; rehearse the phrases “groups of”, “equal to” and “successful because”.
• Challenge confident students to solve reverse problems, such as “How many seconds are in 4 minutes?” and explain why 75 seconds is more than 1 minute but less than 2 minutes. Ask them to create a true and a false statement for a partner.