1. Implementation
Review the mathematical concept.
Review the problem solving steps.
READ: Children read the part that is asking them to find something out.
UNDERSTAND: Children explain what they need to find out.
Children identify what information they will need to find it out.
Remove the coloured rectangle.
Children find the information they need to find it out.
CHOOSE A STRATEGY: Children identify strategies that they could use to find it out.
USE A STRATEGY: Children use a strategy to find it out.
Children record their thinking as they find it out.
CHECK: Children reread the part that asked them to find something out.
Children check that they have found it out.
Children check they have recorded their solution correctly.
Children follow the problem solving steps to solve the 2nd level of the problem, with minimal teacher guidance.
Children who solve the 2nd level, follow the problem solving steps to solve the 3rd level of the problem independently.
Children use the problems as a guide to create their own problem, either alone or in pairs/small groups.
Children solve their own problem.
Throughout the lesson, children share solution strategies.
At the end of the lesson, children explain how they created their own problems.

2. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Mira drew this metric measurement chart.
What unit of measurement is missing?
Mira drew this metric measurement chart.
What unit of measurement is missing?
Mira drew this metric measurement chart.
What unit of measurement is missing?
Measurement and Geometry 57
Create your own problem! Now solve it!

3. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Ronald has a landscaping business.
He bought 1 tonne of white pebbles, and 500 kilograms of gold pebbles.
The total mass of Ronald’s pebbles is:
(a) 1 tonne (b) tonnes (c) tonnes (d) 2 tonnes?
Ronald has a landscaping business.
He bought 1 tonne of white pebbles, and 250 kilograms of gold pebbles.
The total mass of Ronald’s pebbles is:
(a) 1 tonne (b) tonnes (c) tonnes (d) 2 tonnes?
Ronald has a landscaping business.
He bought 1 tonne of white pebbles, and 750 kilograms of gold pebbles.
The total mass of Ronald’s pebbles is:
(a) 1 tonne (b) tonnes (c) tonnes (d) 2 tonnes?
Measurement and Geometry 57
Create your own problem! Now solve it!

4. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
The zoo has 2 elephants. The elephants’ total mass is tonnes.
One elephant’s mass is kilograms.
The mass of the other elephant is:
(a) 3000 kilograms (b) 3000 tonnes (c) 300 kilograms
The zoo has 2 elephants. The elephants’ total mass is tonnes.
One elephant’s mass is kilograms.
The mass of the other elephant is:
(a) 425 kilograms (b) 425 tonnes (c) 4250 kilograms
The zoo has 2 elephants. The elephants’ total mass is tonnes.
One elephant’s mass is kilograms.
The mass of the other elephant is:
(a) 3500 kilograms (b) 35 tonnes (c) 3250 kilograms
Measurement and Geometry 57
Create your own problem! Now solve it!

5. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
The net mass of a can of soup is 370 grams.
The gross mass is 520 grams.
What is the mass of the can?
The net mass of a can of beans is 375 grams.
The can’s mass is 160 grams.
What is the gross mass?
The gross mass of a packet of cereal is 575 grams.
The mass of the packaging is 120 grams.
What is the net mass?
Measurement and Geometry 57
Create your own problem! Now solve it!

6. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
A school bus has a 2500 kg carrying capacity.
How many children could travel on the bus at the same time?
A school bus has a 2800 kg carrying capacity.
How many children could travel on the bus at the same time?
A school bus has a 1800 kg carrying capacity.
How many children could travel on the bus at the same time?
Measurement and Geometry 57
Create your own problem! Now solve it!

7. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Alice has a delivery business.
Each of her trucks can carry 2 tonnes.
A customer buys 780 kilograms of white pebbles, 675 kilograms of gold pebbles and 625 kilograms of black pebbles.
Can the pebbles be delivered on one truck?
Alice has a delivery business.
Each of her trucks can carry 2 tonnes.
A customer buys 380 kilograms of white pebbles, 960 kilograms of gold pebbles and 625 kilograms of black pebbles.
Can the pebbles be delivered on one truck?
Alice has a delivery business.
Each of her trucks can carry 2 tonnes.
A customer buys 780 kilograms of white pebbles, 675 kilograms of gold pebbles and 625 kilograms of black pebbles.
Can the pebbles be delivered on one truck?
Measurement and Geometry 57
Create your own problem! Now solve it!

8. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Which of these is the greatest mass?
(a) 1 tonne and 270 kilograms
(b) tonne
(c) 1265 kilograms
Which of these is the greatest mass?
(a) 1 tonne and 760 kilograms
(b) tonne
(c) 1745 kilograms
Which of these is the greatest mass?
(a) 1 tonne and 240 kilograms
(b) tonne
(c) 125 kilograms
Measurement and Geometry 57
Create your own problem! Now solve it!

9. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Gill needs 1 tonne of sand.
She has 760 kilograms.
How much more sand does she need?
Gill needs 1 tonne of sand.
She has 365 kilograms.
How much more sand does she need?
Gill needs 1 tonne of sand.
She has 825 kilograms.
How much more sand does she need?
Measurement and Geometry 57
Create your own problem! Now solve it!

10. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Susan bought a pile of sand.
After she used of the sand, she had a total of 330 kilograms of sand left.
How many kilograms of sand were in the original pile?
Susan bought a pile of sand.
After she used of the sand, she had a total of 330 kilograms of sand left.
How many kilograms of sand were in the original pile?
Susan bought a pile of sand.
After she used of the sand, she had a total of 330 kilograms of sand left.
How many kilograms of sand were in the original pile?
Measurement and Geometry 57
Create your own problem! Now solve it!

11. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
A packet of biscuits has a net mass of 150 grams and 10 biscuits.
Is the mass of each biscuit closest to
(a) 10 grams (b) 15 grams (c) 20 grams?
A packet of biscuits has a net mass of 150 grams and 8 biscuits.
Is the mass of each biscuit closest to
(a) 10 grams (b) 15 grams (c) 20 grams?
A packet of biscuits has a net mass of 170 grams and 12 biscuits.
Is the mass of each biscuit closest to
(a) 10 grams (b) 15 grams (c) 20 grams?
Measurement and Geometry 57
Create your own problem! Now solve it!

12. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Jill compared the mass of 3 different objects on an equal arm balance.
Which object is the heaviest?
Jill compared the mass of 3 different objects on an equal arm balance.
Which object is the lightest?
Jill compared the mass of 3 different objects on an equal arm balance.
Which object is the heaviest?
Measurement and Geometry 57
Create your own problem! Now solve it!

13. Tonnes, Net and Gross Mass
Problem Solving
Tonnes, Net and Gross Mass
Jill compared the mass of 4 different objects on an equal arm balance.
Which object is the heaviest?
Jill compared the mass of 3 different objects on an equal arm balance.
Which object is the lightest?
Jill compared the mass of 3 different objects on an equal arm balance.
Which object is the heaviest?
Measurement and Geometry 57
Create your own problem! Now solve it!

14. Mass in Grams and Kilograms on Scales
Problem Solving
Mass in Grams and Kilograms on Scales
Maryann had a small object that had a mass heavier than 1 kilogram.
What object could she have?
Oliver had a large object that has a mass of about 1 gram. What object could he have?
Oliver had a small object that has a mass of about 1 gram. What object could he have?
Maryann had a large object that had a mass heavier than 1 kilogram.
What object could she have?
Measurement and Geometry 47
Create your own problem! Now solve it!