Units of time and the calendar
In this topic you will
- Order and compare units of time.
- Record dates using numbers and words.
- Read the date from a calendar.
Key Words
- calendar
- date
- second
- units of time
- weekend
- year
Show Definitions
- calendar: A chart or system that organises days, weeks, and months so we can track time and find dates.
- date: The exact day in a month and year, often written using numbers, words, or both.
- second: A unit of time used to measure very short durations; $60$ seconds make $1$ minute.
- units of time: Standard measures we use to compare and record time, such as seconds, minutes, hours, days, weeks, months, and years.
- weekend: The days at the end of the week when most people do not go to school or work (often Saturday and Sunday).
- year: A unit of time equal to $12$ months (about $365$ days).
Why we learn about time and dates
Time is constantly passing. We need to have an idea of how long things take to plan what we do. We also need to know how to read and write dates so that we can be where we need to be on any day.
EXERCISES
1. Name $3$ things that take about a second.
👀 Show answer
- Blinking your eyes.
- Clapping your hands once.
- Saying a short word (for example, “yes”).
2. Name $3$ things that take about a minute or just a few minutes.
👀 Show answer
- Washing your hands properly.
- Brushing your teeth for about $2$ minutes.
- Making a simple sandwich.
3. Put these units of time in order from the shortest to the longest.
month
minute
day
hour
week
👀 Show answer
minute, hour, day, week, month
4. Draw a line to match the units of time that are the same.
💡 Quick Math Tip
Use a calendar: When you are matching time units or working out a day and date, check a calendar to make sure your answer makes sense.
Use a calendar to help you.
1 year
1 month
1 week
1 hour
60 minutes
7 days
12 months
about 4 weeks
👀 Show answer
- $1$ year = $12$ months
- $1$ month = about $4$ weeks
- $1$ week = $7$ days
- $1$ hour = $60$ minutes
5. Write these dates in numbers only.
The day after Tuesday $4$th January $2022$
The day before Saturday $2$nd February $2019$
👀 Show answer
- $05/01/2022$
- $01/02/2019$
6. Write the circled dates in words.
💡 Quick Math Tip
Include the weekday: When you write a date in words, also write the day of the week (for example, Monday, Tuesday, etc.).
👀 Show answer
- Thursday the twenty-fifth of February two thousand and twenty-one.
- Tuesday the sixteenth of March two thousand and twenty-one.
Think like a Mathematician
February is the only month with $28$ days, $29$ in a leap year.
All the other months have $30$ or $31$ days.
Question: Is there a pattern to how many days there are in each month?
Method:
- Write the months in order from January to December.
- Next to each month, write the number of days it has.
- Look for a repeating pattern in the numbers $30$ and $31$.
- Check your pattern using a calendar.
- Write one clear sentence that describes the pattern you notice.
Show Answers
Pattern idea: After February, the months mostly alternate between $31$ days and $30$ days, with a small change around July and August.
- Months with $31$ days: January, March, May, July, August, October, December.
- Months with $30$ days: April, June, September, November.
- February has $28$ days (or $29$ in a leap year).
Another way to remember: Use your knuckles—each knuckle is a $31$-day month and each dip is a $30$-day month, with February as the special case.
EXERCISES
7. Look at this year’s calendar. In which months will you find these dates?
a. Monday $4$th
b. Wednesday $18$th
c. Saturday $23$rd
👀 Show answer
a. May
b. February, March, November
c. May