General Studies | Hong Kong Transport: Journey Time and Carbon Lesson Plan

2026-11-04

Tutor lesson-prep guides · Primary General Studies

Children know the MTR is faster, but ask how many minutes faster over a week and they say “just faster”. This lesson turns faster into a number using distance over speed.

Objectives — Students can: (1) name four public transport modes and their roles; (2) compute journey time from distance and speed plus waiting time; (3) compare bus and car emissions per kilometre.

01 Prerequisites (3-minute check)

If any of these fails, fix it before the lesson starts.

Skill	Quick check	Pass mark
Time conversion	How many minutes is 0.6 hours?	36 minutes
Division with units	12 km ÷ 20 km/h	0.6 hours
Decimal multiplication	What is 12 × 0.05?	0.6

02 Lesson flow (60 minutes)

Time	Stage	Tutor does	Student does
0–5 min	Hook with the school run	Ask distance and time from home to school	Give time and mode
5–12 min	Quick prerequisite check	Three questions on time conversion	Answer orally
12–22 min	Act 1 Four modes	List MTR, bus, minibus, ferry roles	Choose a mode for three cases
22–30 min	Act 2 Journey time	12 km ÷ 20 km/h plus waiting	Reach 44 minutes by bus
30–36 min	Act 3 Carbon	0.05 versus 0.17 kg per km	Reach 1.44 kg difference
36–50 min	Timed practice (14 min)	Two questions, seven minutes each	Work independently
50–55 min	Peer review	Swap and check waiting time	Spot a missing wait
55–60 min	Exit check	Three oral questions	Recompute if wrong

03 Teaching script (read it out)

Scene 1: Four modes, four jobs

List MTR, franchised bus, minibus and ferry. Ask which one reaches an outlying island, which one crosses districts for work, which one covers a three-minute trip from home.
The answer is not “the MTR is best”; each mode fits a distance, a load and a terrain. Ferries exist because there is no track across the harbour.

Students pick one mode for each of three situations with a reason.

Scene 2: Distance over speed, plus waiting

12 km at an average 20 km/h is 0.6 hours, or 36 minutes. Add 8 minutes waiting: 44 minutes by bus.
The MTR at 40 km/h is 18 minutes, plus 5 minutes walking and 3 minutes waiting: 26 minutes. The gap is 18 minutes; two trips a day for five days is 180 minutes, three hours a week.

Students compute 18 minutes and 3 hours and state that waiting must be added.

Scene 3: Same trip, triple the carbon

A car emits about 0.17 kg CO2 per km; a bus about 0.05 kg per passenger km. Over 12 km that is 2.04 kg versus 0.6 kg, a difference of 1.44 kg, more than three times.
Then ask whether everyone should take the bus: frequency, late-night gaps and route coverage are real limits.

Students reach 1.44 kg and name one difficulty with buses.

04 Question types and worked steps

Type	Example	Steps	Answer
Choose a mode	Island, cross-district, short hop	Match distance and load	Ferry, MTR, walk or minibus
Journey time	12 km at 20 km/h, wait 8 min	Distance ÷ speed × 60 + wait	44 minutes
Compare time	Versus 26 minutes by MTR	Subtract, then multiply trips and days	Saves 3 hours a week
Carbon	12 km car versus bus	Factor × distance	2.04 vs 0.6 kg

Sanity check (teach this): Check the numbers: 12 km at 20 km/h is 36 minutes, plus 8 waiting, so 44 minutes by bus. The MTR takes 18 minutes plus 5 walking and 3 waiting, so 26. The gap is 18 minutes, which is 180 minutes or 3 hours across five return days. Carbon is 2.04 kg versus 0.60 kg, a 1.44 kg gap.

05 Independent practice (3 questions)

Question	Answer	What to watch
Choose three	Pick a mode for three situations	Every choice needs a reason
One trip	8 km at 16 km/h, wait 10 min	Must reach 40 minutes
One week	Save 20 minutes a day for five days	Must reach 100 minutes

06 Common mistakes and what to say

Mistake	Student writes	Say this
Ignoring the wait	“The bus takes 36 minutes”	“You still have to wait; the trip is 44 minutes.”
Multiplying speed	“12 × 20 = 240 minutes”	“Distance is divided by speed, not multiplied.”
Hours left as hours	Writing 0.6 as 0.6 minutes	“0.6 is hours; multiply by 60 for minutes.”
Carbon only	“So the bus is always best”	“Late nights, frequency and routes count too.”

07 Homework (paper, section and question numbers)

P4 General Studies paper — Society and citizenship short answers: facilities and transport
P5 General Studies paper — Data questions: compare two journeys
Primary General Studies index — All chapters and matching papers

08 Exit check (last 5 minutes)

Question	Answer	Decision
Why a ferry to an outlying island?	No road or rail across the water	“Because it is faster” means re-teach
How do you compute journey time?	Distance over speed plus waiting	Missing wait means re-teach
Bus versus car carbon?	About three times less, 1.44 kg on 12 km	“About the same” means recompute

09 Tutor FAQ

Must children memorise the MTR map?

No; the roles and the time sum matter, and the map can be looked up.

Why is a bus lower carbon than a car?

One trip carries many more people, so fuel and emissions are shared.

Should traffic jams be included?

Yes, which is why average speed is used and the answer is called an estimate.

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A TutorZone lesson-prep guide. Written by the TutorZone team; questions and lesson flow are original and are not taken from any school or publisher material.