Class 4 Maths Chapter 12 Ticking Clocks and Turning Calendar – Revision Notes

Class 4 Maths Chapter 12, Ticking Clocks and Turning Calendar, covers two closely related life skills — reading time on a clock and reading dates on a calendar — along with calculating durations and elapsed time.

Last Updated: September 23, 2026

About Chapter 12: Ticking Clocks and Turning Calendar

Time is one of the most practical maths topics children use every single day, from checking the school bell to planning a birthday. This chapter strengthens both analogue clock reading and calendar literacy, then connects the two through duration problems.

Key Concepts

1. Reading a Clock

An analogue clock has an hour hand (shorter) and a minute hand (longer). Reading time means noting where the hour hand points (approximately) and where the minute hand points exactly, then combining them — such as 4:35, read as “twenty-five minutes to five” or “four thirty-five”.

2. AM and PM

A full day has 24 hours, split into AM (12 midnight to 12 noon) and PM (12 noon to 12 midnight). The same clock face is used twice a day, so AM/PM tells us which half of the day is meant.

3. Calculating Duration

Duration is the amount of time that passes between a start time and an end time. It is found by subtracting the start time from the end time, being careful when the calculation crosses over an hour (60 minutes = 1 hour).

4. Reading a Calendar

A calendar shows days, weeks, and months of the year. Key facts: 7 days make a week, most months have 30 or 31 days (except February, which has 28 or 29 in a leap year), and 12 months make a year.

5. Leap Years

A leap year has 366 days instead of 365, with an extra day added to February (29 instead of 28). Leap years usually occur every 4 years.

6. Days, Weeks, Months, Years

Understanding the relationship between these units — 7 days in a week, about 4 weeks in a month, 12 months in a year — helps in solving calendar-based word problems, like finding a date a certain number of days after today.

Quick Recap

• The hour hand is shorter; the minute hand is longer on an analogue clock.
• AM covers midnight to noon; PM covers noon to midnight.
• Duration = end time minus start time, remembering 60 minutes make 1 hour.
• A week has 7 days; most months have 30 or 31 days; February has 28 (or 29 in a leap year).
• A leap year occurs roughly every 4 years and has 366 days.

Common Mistakes to Avoid

Students often mix up the hour and minute hands, especially when they are similar in length on some clock faces — always check which hand is shorter (hour) before reading the time. In duration problems, a common mistake is subtracting minutes as if there were 100 minutes in an hour instead of 60, leading to incorrect answers when borrowing across the hour.

How to Practise This Chapter at Home

Use a real analogue clock or clock face model to practise reading random times throughout the day, and ask duration questions like “how long until dinner?” Look at a real calendar and practise finding what day of the week a certain date falls on, or how many days remain until an upcoming event or birthday.

Why This Chapter Matters

Time management and calendar literacy are lifelong practical skills, used in scheduling, planning, punctuality, and everyday communication. This chapter also builds a foundation for later, more complex time-based calculations in maths and science.

Frequently Asked Questions

What is the easiest way to teach clock reading?
Start with the hour hand only (identifying the nearest hour), then add the minute hand gradually, practising with a real or model clock regularly.

How do you calculate duration across an hour, like from 2:45 to 3:20?
Break it into parts: from 2:45 to 3:00 is 15 minutes, then from 3:00 to 3:20 is 20 more minutes, giving a total duration of 35 minutes.

Why do we have leap years?
Because a full year is actually about 365.25 days, so an extra day every 4 years keeps the calendar aligned with the Earth’s orbit around the sun.

How can a child remember which months have 30 or 31 days?
A common trick is counting knuckles on a fist — each knuckle and the gap between represents a month, where knuckles are 31-day months and gaps are 30-day months (with February as the exception).

Why is understanding AM and PM important?
Because the same clock time (like 7:00) can mean two very different moments in a day — morning or evening — and AM/PM removes that confusion.

See the Chapter 12 Solutions for the full textbook walkthrough.

Written by Satish

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