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Lesson preview: Fractions: Parts, Equivalence and Comparing

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Equivalent fractions

  • 1/2, 2/4 and 4/8 shade the same amount
  • Multiply top and bottom by the same number to find one
  • Divide top and bottom by the same number to simplify

Visual: Three bars of the same length showing one half, two quarters and four eighths. The shaded part ends at the same place on every bar, showing the three fractions are equal.

Splitting every part in two doubles both the number of parts and the number shaded, so the amount stays the same. That is why you multiply the top and the bottom by the same number.

Worked example

Write 12/18 in its simplest form

  • Find a number that divides both 12 and 18: the biggest is 6
  • 12 ÷ 6 = 2 and 18 ÷ 6 = 3
  • So 12/18 = 2/3
  • Check: 2 and 3 have no common factor except 1

A fraction is in its simplest form when the top and bottom have no common factor except 1. Dividing by the highest common factor gets there in one step.

Comparing fractions

  • Hard to see: is 2/3 bigger than 3/5?
  • Write both with the same denominator: 15
  • 2/3 = 10/15 and 3/5 = 9/15, so 2/3 is bigger

Visual: Two bars show two thirds and three fifths, which look almost the same length. Both are then split into fifteenths: two thirds becomes ten fifteenths and three fifths becomes nine fifteenths, so two thirds is bigger.

When the denominators are the same, compare the numerators. A common denominator turns a hard comparison into an easy one.

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Complete lessons with slides, speaker notes, a quiz and downloads. The first has moving, interactive diagrams on every key slide.

Science

Fractions: Parts, Equivalence and Comparing

A visual maths lesson for ages 11–12 on fractions: equal parts of a whole, numerators and denominators, fractions on a number line, equivalent fractions, comparing and ordering, and fractions of amounts. Interactive fraction builder, speaker notes and a 5-question quiz. Ages 11–12 15 slides 50 min Interactive diagramsStart the lesson

Photosynthesis: How Plants Make Food

A ready-to-teach biology lesson for ages 13–16 on photosynthesis: the word and balanced equations, how a leaf is built for the job, limiting factors and what plants do with glucose. Speaker notes on every slide, a 5-question quiz and a worksheet. Ages 13–16 17 slides 45 min Interactive diagrams

Acids, Bases and the pH Scale

A ready-to-teach chemistry lesson for ages 12–15 on acids, bases and alkalis: the pH scale, litmus and universal indicator, everyday examples, neutralisation and how to name salts, with a safe indicator practical. Ages 12–15 16 slides 45 min

Electric Circuits: Current, Voltage & Resistance

A ready-to-teach physics lesson for ages 12–15 on electric circuits: current, potential difference (voltage), resistance and Ohm's law, how to use ammeters and voltmeters, and the rules for series and parallel circuits. Ages 12–15 14 slides 45 min

Move the sliders. Watch the graph answer.

Why does a plant in bright light stop speeding up? Change the light, carbon dioxide and temperature and see which one holds photosynthesis back. This is slide 10 of the photosynthesis lesson, exactly as students use it.

Open it in the lesson

Rate: 52% of the model’s maximum. Limiting factor now: light intensity.

Simplified model: it shows the shapes of the graphs, not measured values. The best temperature differs from plant to plant.

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How living things get energyFrom the cell to the whole organism: where food comes from and how energy is released from it.3 lessons in orderMatter and chemical reactionsParticles first, then what happens when substances react, measured and written as equations.3 lessons in orderForces, electricity and motionThree physics lessons in rising difficulty: forces, then circuits, then motion graphs and equations.3 lessons in orderNumber and proportionNegative numbers, then the proportional thinking behind percentages and ratios.3 lessons in order

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17 school lessons so far, each checked against its sources before publishing.

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Fractions: Parts, Equivalence and ComparingPublished 15 Oct 2026Acids, Bases and the pH ScalePublished 1 Oct 2026Electric Circuits: Current, Voltage & ResistancePublished 1 Oct 2026Forces and Newton's Laws of MotionPublished 1 Oct 2026PercentagesPublished 1 Oct 2026Photosynthesis: How Plants Make FoodPublished 1 Oct 2026

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