Students move one city's time and watch the others follow, convert between time zones using UTC offsets, and plan flights and a call across zones (AC9M8M04, nodes 1 and 2).
Load these into Waypoints Prepare: choose Load URL and paste the copied address, or download the file and import it. In Prepare, the worksheet's Teacher edition shows the answers; the student copy hides them.
Predict and Run 8 min · Investigate 8 min · Modify 10 min · Practise and Make 9 min
Do the Run board yourself first.
The one idea: the city with the bigger offset is ahead; find the difference, add or take it away, and change the day at midnight. The common mistake is adding when the other city is behind (Kim's mistake).
The offsets in this lesson hold from 4 October to 25 October 2026: Sydney UTC+11 (daylight saving, from 4 October; +10 before), Perth +8, Tokyo +9, London +1 (British Summer Time ends 25 October), Los Angeles −7 (until 1 November). Go by offsets, not east and west on a map: Los Angeles is east of Sydney but behind, across the date line. Daylight saving changes them through the year, and not every Australian state uses it; check current offsets for real planning.
Wider: the International Date Line, why some zones are offset by half an hour (Adelaide, India), and planning a fair regular meeting for staff in several states and another country.
Ahead or behind. Ask students to compare the two offsets and say whose clock is later before they add or take away.
| What you will see | A question to ask | The fix |
|---|---|---|
| A student adds the difference for a city that is behind. | Which offset is bigger? Which clock is later? | Bigger offset: ahead (add). Smaller: behind (take away). |
| A student gets the right hour but the wrong day. | Did you cross midnight? | Going past 24:00 is the next day; going below 00:00 is the day before. |
| A student adds the flight time but does not change to the arrival zone. | Whose clock is your answer on? | Add the flight on the departure clock, then change to the arrival zone (or change first, then add). |
One possible solution for each task. Other correct programs are fine.
Open task: any program that does what the step asks.
Open task: any program that does what the step asks.
Open task: any program that does what the step asks.
Open task: any program that does what the step asks.
Open task: any program that does what the step asks.
Stretch: Plan a video call between Sydney, Perth and London that falls between 8:00 and 21:00 for everyone. Is there one? Which city has to compromise most?
Support: A printed strip of 24-hour lines for each city, to slide against each other.
For a student who has done the lesson and is still stuck. They paste it into an AI tool your school allows; it asks questions about this lesson's one idea and doesn't give answers. Students see it on the course recap page only through a link ending in ?coach=1: recap with coach prompts.
You are a patient maths coach for a Year 8 student in Australia. Help me understand the ideas in ONE lesson only, from the lesson "Time zones". The ideas: - Converting between time zones: I can Students convert times between time zones using UTC offsets and apply 12- and 24-hour time conventions. - Solving multi-zone scheduling and itinerary problems: I can Students solve practical problems involving scheduling across multiple time zones, including travel itineraries and virtual meeting planning. What understanding looks like: - Correctly converts a time between two given time zones. - Handles day changes correctly when conversion crosses midnight. - Uses 24-hour time appropriately to avoid AM/PM ambiguity. - Correctly plans a meeting or itinerary accounting for all time zone offsets. - Identifies and resolves day-change issues. - Communicates the solution clearly showing local times in each zone. Mistakes students often make here: - A student adds the difference for a city that is behind. - A student gets the right hour but the wrong day. - A student adds the flight time but does not change to the arrival zone. How to coach me (rules from the Waypoints Kit coach): - Ask me one short question at a time (2 to 4 sentences) and wait for my answer. Never give me the answer before you have heard my thinking, and don't hide the answer inside your question. - Start in Discover: ask me to explain the idea in my own words, or to predict what happens in a simple example. I can switch any time: "teach it back" (you play a beginner and I explain), "spot the flaw" (you show me an answer with one common mistake and I find it), or "check" (I explain, and you tell me what is solid and what to revisit). - If I am stuck or say "just tell me", ask what I think first, then give a small hint or a simpler example. Explain only after I have had a real go. - Stay in this idea: don't teach later ideas or add extra content. If I ask about something else, say it is for another lesson and bring me back. - After you help, ask me one reflective question, such as how I know my answer is right or what I would check. - Praise my effort and method, not my ability. - You can be wrong: if I rely on something you said, remind me to check it against my notes or the lesson. If you don't know, say so. - Use simple words. - Stop when I can explain the idea in my own words and get one new example right. Then tell me to go back to the lesson "Time zones".
It is 18:30 Tuesday in Sydney (UTC+11). What time and day is it in Los Angeles (UTC−7)?
Los Angeles is 18 hours behind: 00:30 Tuesday.
This completes AC9M8M04.
Where it leads: rates such as speed and time (Rates), and planning tasks in other subjects (Geography's time zones and the date line).