Primary 6 Maths: Averages and Line Graphs

Primary 6 Maths: Averages and Line Graphs — Tutor Lesson Plan

2026-10-27

Tutor lesson-prep guides · Primary maths

The average is not “the middle number”. Level the blocks first, then use total ÷ count, then read the trend rather than the last point.

Objectives — the student can compute a mean as total ÷ count, work back from a mean to a total, and describe a line graph by its highest, lowest and overall trend.

01 Prerequisites (3-minute check)

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

Skill	Quick check	Pass mark
Addition and division	8+9+10+11+12, then ÷ 5	50 and 10
Reading graphs	Which bar is tallest?	Read the axis
Sharing equally	12 sweets among 3	4 each

02 Lesson flow (50 minutes)

Time	Stage	Tutor does	Student does
0-8 min	Levelling	Stack blocks of different heights and level them	Describe the level height
8-18 min	Mean	Average five numbers	One set alone
18-28 min	Total from mean	Mean 15 over 6 values	One alone
28-40 min	Line graph	Highest, lowest and trend	One sentence on the trend
40-46 min	Fix errors	Board “read the last point only”	Say what was missed
46-50 min	Exit check	Three questions marked at once	Finish alone

03 Teaching script (read it out)

Scene 1: Average means levelled out

Sales of 8, 12, 10 and 10 total 40, and 40 ÷ 4 = 10.
It means: if every day were the same, it would be 10 a day.

Student states “add them up, divide by how many there are”.

Scene 2: Total from an average: multiply

A mean of 15 across 6 people means 15 × 6 = 90 in total.
For “what does the fourth day need”, find the target total and subtract what is known.

Student does 36 over three days, target 52 over four: 16 needed.

Scene 3: Line graphs: describe the whole line

Say three things: the highest point, the lowest point, and whether the line rises or falls overall.
Answering from the last point alone is wrong.

Warn: if the time axis is uneven, slopes cannot be compared directly.

04 Question types and worked steps

Type	Example	Steps	Answer
Find the mean	8, 9, 10, 11, 12	Total ÷ 5	10
Total from mean	mean 15, 6 values	15 × 6	90
Missing value	36 over 3 days, want 13 over 4	52 − 36	16
Read a line graph	highest and lowest	Read the axis, then the whole line	from the graph

Sanity check (teach this): A mean always lies between the smallest and largest values; a mean of 20 from data topping out at 12 is an arithmetic error.

05 Independent practice (3 questions)

Question	Answer	What to watch
Mean of 8, 9, 10, 11, 12	10	All five added
Total when mean 15 over 6	90	Multiplying
Describe the trend	from the graph	Whole line, not one point

06 Common mistakes and what to say

Mistake	Student writes	Say this
Median called the mean	picks 10 out of the list	Add them all and divide.
Wrong count	dividing five values by 4	Divide by how many values there are.
Dividing to find a total	mean 15 over 6 gives 15 ÷ 6	Multiply to get a total.
Reading only the last point	answers “always rising”	Give highest, lowest and the overall trend.

07 Homework (paper, section and question numbers)

Primary 6 first-term paper — Section D, questions 1 to 3
Primary 6 first-term paper — Section D, questions 7 and 8

08 Exit check (last 5 minutes)

Question	Answer	Decision
Mean of 8, 9, 10, 11, 12	10	All right: statistics complete
Total when mean 15 over 6	90	One wrong: re-teach the reverse step
Fourth day needed for a mean of 13	16	Two wrong: repeat the levelling activity

09 Tutor FAQ

Median and mode too?

Not in Primary 6; they come in Secondary 1.

Line graph or bar chart?

Bar charts compare, line graphs show change; the same data can use either.

Calculators?

Not here: the arithmetic is part of the skill.

Find a tutor — free

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.