Primary 1 Maths | Hong Kong Coins Teaching Guide | Seven Coins, 1 Dollar = 10 Ho and Change

2026-11-09

Tutor lesson-prep guides · Primary Maths

A child can name a one-dollar coin but calls a 50-cent coin and a one-dollar coin “both one dollar”. This lesson keeps one line: name the value, then 1 dollar equals 10 ho, then pay and give change.

Objectives — Students can: (1) name the value of all seven circulating coins and order them from smallest to largest; (2) convert using 1 dollar equals 10 ho, for example 5 dollars equals five 1-dollar coins or ten 50-cent coins; (3) pay an amount with the fewest coins and work out change within 10 dollars.

01 Prerequisites (3-minute check)

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

Skill	Quick check	Pass mark
Numbers to 20	Count from 1 to 20 and write the numerals	Counts forwards and backwards
Addition	What is 7 plus 8	15
Comparing	Which is larger, 50 or 100	100

02 Lesson flow (60 minutes)

Time	Stage	Tutor does	Student does
0-6 min	Sorting	Hand out a pile of coins and ask for two piles: ho and dollars	Sort by hand
6-18 min	Name the coins	10, 20, 50 ho then 1, 2, 5, 10 dollars; read each aloud	Read and write each value
18-32 min	Equivalent values	1 dollar equals 10 ho; build 1 dollar from 50-cent coins	Build three amounts
32-44 min	Paying	A pencil costs 3 dollars 50; how do you pay	Pay with fewest coins
44-54 min	Change	Pay 5 dollars, what change and which coins	Work out and lay out coins
54-60 min	Exit check	Three questions collected and marked	Work independently

03 Teaching script (read it out)

Scene 1: Two piles first, values second

Start with a pile of coins and ask the child to sort into ho and dollars. That single action makes the unit visible. There are seven circulating coins: 10, 20 and 50 ho, then 1, 2, 5 and 10 dollars. The large numeral is the face value and the unit follows it.
All seven together make 18 dollars 80 cents, or 1880 cents, which is worth adding up aloud as number practice.

Students do: line the seven coins up from smallest to largest and read each value.

Scene 2: One dollar equals ten ho: build it, do not chant it

The whole idea is one sentence: 1 dollar is 10 ho. So two 50-cent coins make a dollar, five 20-cent coins make a dollar, and ten 10-cent coins make a dollar.
Method: skip the table and let them build it with real coins, once for 1 dollar, then 2 and 5 dollars. With 10, 20, 50 and 100-cent coins there are 11 different ways to make one dollar; adding the 2-dollar coin gives 41 ways to make two dollars. The number is not for memorising; the point is that many routes reach the same value.

Students say: how many 50-cent coins make 5 dollars, and how many 1-dollar coins, and whether both answers agree.

Scene 3: Pay big first, then subtract for change

The paying order is fixed: largest denomination first, then smaller ones to fill the gap. A pencil at 3 dollars 50 takes 2 dollars plus 1 dollar plus 50 ho, three coins.
Change is two steps: subtract first (500 minus 350 cents equals 150 cents), then lay out the coins (100 plus 50 cents). At Primary 1 avoid the word cents; say 3 dollars 50 and 1 dollar 50.

Students do: an eraser costs 2 dollars 50, pay with 5 dollars, say the change and which two coins.

04 Question types and worked steps

Type	Example	Steps	Answer
Naming values	Write the value of each coin shown	Read the numeral, then the unit	Always include the unit
Equivalent values	How many 50-cent coins make one dollar	Use 1 dollar equals 10 ho as the bridge	Answer as a count of coins
Paying	Pay an amount with fewest coins	Start from the largest coin	Fewest coins wins
Change	Amount paid and change due	Subtract, then lay out coins	Change is smaller than the payment

Sanity check (teach this): Sanity check: the smallest circulating coin is 10 ho, there is no 1-ho coin in use; the seven coins total 18 dollars 80 cents, not 18 dollars 8 ho; change is always smaller than the payment; 1 dollar is 10 ho, not 100 ho.

05 Independent practice (3 questions)

Question	Answer	What to watch
Order the coins	Seven coins smallest to largest	Check 50 ho sits below 1 dollar
Build a dollar	Three different ways to make 1 dollar	Each way must use real coins
Pay an amount	3 dollars 50 with fewest coins	Count the coins used
Change	Pay 10 dollars for 6 dollars 50	Write the change and coin set

06 Common mistakes and what to say

Mistake	Student writes	Say this
Reading 50 ho as 5 dollars	That one is five dollars	The coin says 50; what is the unit written after it?
Saying 1 dollar is 100 ho	One dollar is one hundred points	How much is one ho, and what do ten of them make?
Grabbing random coins	A fistful of 10-cent coins for 3 dollars 50	Start with the largest; can you use 2 dollars, then what is left?
Change larger than payment	Pay 5 dollars and get 6 dollars change	You handed over 5 dollars, so how can the change be more? Subtract again.

07 Homework (paper, section and question numbers)

Primary maths chapter index — All chapters by level
Teaching guide index — Same structure, other subjects
Redo this chapter — Questions 1 to 4 again, writing the coin set each time

08 Exit check (last 5 minutes)

Question	Answer	Decision
The seven coins	10, 20, 50 ho and 1, 2, 5, 10 dollars	Missing one means back to act one
One dollar in ho	10 ho	Answering 100 ho means act two again
Pay 5 dollars for 3 dollars 50	1 dollar 50, using a 1-dollar and a 50-cent coin	Wrong answer means act three again

09 Tutor FAQ

Must they memorise 1 dollar equals 10 ho?

Yes, it is the root of every conversion. But make them build it with coins once; hands-on memory lasts longer than a chanted sentence.

Should we teach the 1-ho coin?

No. It is no longer minted or in circulation; teaching the seven live coins avoids confusion at a real counter.

Is cash still worth teaching?

Yes. School work and public exams test coin values and change, and coins are the most concrete place-value practice available.

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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.