Mathematics · Year 5

Active learning ideas

Time: 12-hour and 24-hour Clocks

Active learning helps students grasp 12-hour and 24-hour clocks because it transforms abstract time notation into concrete, visual, and collaborative experiences. Moving clocks, matching cards, and team challenges make the conversion process tangible, reducing confusion about AM/PM and 24-hour cycles.

• National Curriculum Attainment Targets
• KS2: Mathematics - Measurement

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Think-Pair-Share
• 20 min · Pairs

Card Sort: Time Matches

Prepare cards with 12-hour times on one set and 24-hour equivalents on another. Pairs sort and match them, discussing conversions like 2 PM to 14:00. Groups then create and swap new cards for peers to match.

Explain the advantages of using a 24-hour clock in certain contexts.

Facilitation Tip

For Card Sort: Time Matches, provide physical or digital cards with mismatched times to force students to physically manipulate and compare formats.

What to look for

Present students with a list of times, some in 12-hour format (e.g., 7:15 AM, 10:30 PM) and some in 24-hour format (e.g., 02:00, 18:45). Ask them to write the equivalent time for each, ensuring correct AM/PM usage or 24-hour notation.

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 02

• Think-Pair-Share
• 35 min · Small Groups

Timetable Build: Dual Formats

Small groups design a school day timetable using both 12-hour and 24-hour notations. They convert entries collaboratively and present to the class, justifying choices like using 24-hour for buses. Include breaks and lessons with start and end times.

Differentiate between 3 PM and 03:00.

Facilitation Tip

In Timetable Build: Dual Formats, give each group a blank template with mixed time formats so they must negotiate and agree on the correct conversions.

What to look for

Ask students: 'Imagine you are planning a video call with a friend in a different country. Why is it important to know how to convert between 12-hour and 24-hour clocks? What problems could arise if you didn't?'

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 03

• Think-Pair-Share
• 25 min · Small Groups

Conversion Relay: Team Challenge

Divide into small groups for a relay: teacher calls a time in one format, first student converts aloud and tags next teammate. Include variations like timetable entries. Winning team has most accurate conversions.

Construct a timetable entry using both 12-hour and 24-hour formats.

Facilitation Tip

During Conversion Relay: Team Challenge, position a large clock face visible to all teams to reinforce the visual link between analog and 24-hour notation.

What to look for

Provide each student with two scenarios: 'A train departs at 14:20' and 'School finishes at 3:30 PM'. Ask them to write the time for each scenario in the *other* format (e.g., 14:20 becomes 2:20 PM, 3:30 PM becomes 15:30).

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 04

• Think-Pair-Share
• 30 min · Pairs

Clock Role-Play: Announcements

Pairs role-play as train announcers, converting and stating times in both formats for a journey schedule. Switch roles and add audience questions on advantages. Record for self-review.

Explain the advantages of using a 24-hour clock in certain contexts.

Facilitation Tip

For Clock Role-Play: Announcements, assign roles that require students to read times aloud in both formats, ensuring verbal and written practice.

What to look for

Present students with a list of times, some in 12-hour format (e.g., 7:15 AM, 10:30 PM) and some in 24-hour format (e.g., 02:00, 18:45). Ask them to write the equivalent time for each, ensuring correct AM/PM usage or 24-hour notation.

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

A few notes on teaching this unit

Teach 12-hour and 24-hour clocks by connecting them to students’ daily lives, using analog clocks to scaffold understanding before moving to abstract notation. Avoid rushing to algorithmic rules; instead, let students discover patterns through guided exploration. Research shows that kinaesthetic and collaborative tasks improve retention and accuracy more than worksheets alone.

By the end of these activities, students will confidently convert times between formats, explain when to use each, and apply conversions in real-world contexts like timetables and schedules. Look for accurate conversions, clear explanations, and students’ ability to justify their choices during peer discussions.

---

Watch Out for These Misconceptions

• During Card Sort: Time Matches, watch for students who incorrectly pair 12 PM with 24:00.

  Have these students physically place 12 PM on the noon position of an analog clock and confirm it matches 12:00 in 24-hour format, then move to midnight at 00:00.

• During Clock Role-Play: Announcements, listen for students adding AM/PM labels to 24-hour times.

  Prompt them to read their schedule aloud without labels, then ask peers to verify if the 24-hour notation stands alone correctly.

• During Conversion Relay: Team Challenge, notice teams that add 12 to 12 PM or go past 23:59.

  Stop the team, show them the 12 PM position on a clock, and ask them to convert 12 PM and 1 PM together using the ‘add 12’ rule, stopping at 23:59.

---

Methods used in this brief

• Think-Pair-Share