Grade 6 Mathematics
Build your mathematical reasoning and problem-solving skills.
Unit Outline
Geometry — Volume & Capacity
We are learning to calculate perimeter, area, surface area, and volume, and to convert between volume and capacity.
Your Learning Journey
Assessment Criteria
All MYP Mathematics assessments are marked against four criteria (A–D), each scored 1–8. Here is what each level looks like.
Knowing and Understanding
Select and apply mathematical techniques to solve problems.
Attempts to use mathematical knowledge but with frequent errors.
Applies mathematical knowledge to solve routine problems. Some errors in complex situations.
Selects and applies appropriate mathematical knowledge to solve problems accurately.
Selects and applies mathematical knowledge with precision in both familiar and unfamiliar situations.
Investigating Patterns
Select and apply mathematical problem-solving techniques, describe patterns, and make generalisations.
Identifies simple patterns when given guidance.
Applies problem-solving techniques, describes patterns, and attempts a general rule.
Applies techniques to find patterns, describes and verifies general rules.
Discovers complex patterns, proves general rules, and justifies conclusions with mathematical reasoning.
Communicating
Use correct mathematical language, notation, diagrams, and conventions.
Shows some working. Uses basic mathematical language.
Shows working with some organisation. Uses some mathematical notation correctly.
Shows clear, well-organised working. Uses correct notation and diagrams consistently.
Communicates mathematical thinking with precision, clarity, and sophisticated use of notation.
Applying Mathematics in Real Life
Transfer mathematical knowledge to real-life situations and discuss the degree of accuracy.
Identifies a real-life context but struggles to apply mathematics to it.
Applies mathematics to a real-life situation and discusses the result.
Models a real-life situation mathematically, discusses accuracy, and draws conclusions.
Creates sophisticated mathematical models for real-life problems, critically evaluates accuracy and limitations.
Lesson Slides
Worksheets
Review Games
Videos
Key Vocabulary
Essential terms for this unit. Use these to build your mathematical vocabulary.
Perimeter & Area
The total distance around the outside of a 2D shape. Measured in cm, m.
The amount of space inside a 2D shape. Measured in squared units (cm², m²).
The perimeter of a circle. C = 2πr or C = πd.
The ratio of a circle's circumference to its diameter. Approximately 3.14159.
The vertical distance at 90° from the base. Must use this (not the slant) in area formulas.
3D Shapes & Volume
The total area of all faces of a 3D shape. Imagine unfolding it into a flat net.
The amount of space inside a 3D shape. Measured in cubed units (cm³, m³).
How much liquid a container can hold. 1 cm³ = 1 mL (the golden rule).
A 3D shape with the same cross-section along its entire length. Volume = area of cross-section × length.
A flat pattern that folds up to make a 3D shape. Used to calculate surface area.
🚀 Extension Activities
Go beyond the textbook. Choose an activity that interests you and challenge yourself.
Dream Bedroom Designer
Design ChallengeDesign your dream bedroom on graph paper. It must fit inside a 5m × 4m room. Calculate the perimeter, area of the floor, and volume of the room. Include furniture with real measurements. Calculate how much paint you need for the walls.
Famous Buildings Measurement Challenge
Research & CalculationResearch the dimensions of 3 famous buildings: Nanjing's Zifeng Tower, Seoul's Lotte World Tower, and Berlin's TV Tower. Calculate the volume of each (approximate as rectangular prisms). Which has the greatest volume? Create a comparison infographic.
Gift Wrapping Olympics
Practical ChallengeBring 3 different-shaped boxes to class. Measure each one, calculate the exact surface area, then cut wrapping paper to those exact dimensions. Who can wrap their boxes with the least wasted paper?
Pool Capacity Investigation
Real-World MathsThe NIS pool is 25m × 16m × 1.6m deep. Calculate: How long would it take to fill using a garden hose (15 L/min)? How many students could swim at once if each needs 5m² of space? How much would it cost to heat at ¥0.05 per litre per degree?
Explore
Interactive simulations and tools. Use these to deepen your understanding.
Area Builder
PhET SimulationBuild shapes on a grid and discover the relationship between dimensions and area.
GeoGebra 3D Calculator
GeoGebraBuild 3D shapes and rotate them. Visualise how surface area wraps around a shape and how volume fills the inside.
↗ Open ToolUnit Rates
PhET SimulationPractice converting between units — a key skill when converting between volume (cm³) and capacity (mL, L).
Desmos Scientific Calculator
DesmosUse this calculator for area and volume calculations involving π.
↗ Open ToolSelf-Quiz
Click a question to reveal the answer.
What is perimeter?
The total distance around the outside of a 2D shape.
What is the formula for the circumference of a circle?
C = 2πr or C = πd.
What is the formula for the area of a triangle?
A = ½ × base × perpendicular height.
Why must you use the PERPENDICULAR height, not the slant side?
The perpendicular height is the true vertical distance from base to top (at 90°). The slant side is longer and gives the wrong answer.
What is surface area?
The total area of ALL the faces of a 3D shape. Imagine unfolding it into a flat net.
What is the formula for the surface area of a rectangular prism?
SA = 2(lw + lh + wh).
What is volume?
The amount of space inside a 3D shape. Measured in cubed units (cm³, m³).
What is the formula for the volume of a triangular prism?
V = area of triangle × length = (½ × b × h) × l.
What is the golden rule for capacity?
1 cm³ = 1 mL (exactly).
Convert 1 m³ to litres.
1 m³ = 1,000 L.
A fish tank is 50cm × 30cm × 40cm. How many litres does it hold?
V = 60,000 cm³ = 60,000 mL = 60 L.
A cube has side length 6 cm. Find its volume and surface area.
Volume = 6³ = 216 cm³. Surface area = 6 × 6² = 216 cm².
What is the area of a circle with radius 5 cm?
A = πr² = π × 25 ≈ 78.5 cm².
What is a prism?
A 3D shape with the same cross-section along its entire length — like slicing bread, every slice is the same.
Common mistake: using the slant height instead of perpendicular height. Why does this give the wrong answer?
The slant height is longer than the perpendicular height. Using it overestimates the area because the formula assumes a 90° angle at the base.
A swimming pool is 25m × 10m × 2m. How many litres of water does it hold?
V = 25 × 10 × 2 = 500 m³. 1 m³ = 1000 L. So 500 × 1000 = 500,000 L.
Two shapes have the same area. Must they have the same perimeter? Explain.
No. A 4×4 square (area 16, perimeter 16) and a 2×8 rectangle (area 16, perimeter 20) have the same area but different perimeters.
Maths Toolkit
Useful tools and references for your mathematical work.