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1. Science and Technology K–6 · Years 1–2

   Bend, twist, stretch and fold: changing materials without changing what they are

   Physical actions change a material's shape, and some changes spring back while others stay, but the material stays the same stuff.

   PracticalLow risk

2. Science and Technology K–6 · Years 1–2

   Mixing and separating: sand, rice and paper clips

   Materials can be mixed without changing what they are, and a mixture can be taken apart again using differences such as size and magnetism.

   PracticalLow risk

3. Science and Technology K–6 · Year 2

   Breaking into smaller pieces: crushed chalk is still chalk

   Snapping and crushing chalk makes smaller and smaller pieces without making a new material: the powder marks paper the same way, the pieces still add up to the same length, and the sealed bag weighs the same at every step.

   PracticalLow risk

4. Science and Technology K–6 · Year 3

   Chocolate, butter, wax and ice: different solids melt at different temperatures

   Each solid changes to a liquid at its own temperature, so a warm-water bath with a thermometer lets a learner read off the melting temperature of several everyday materials.

   PracticalLow risk

5. Science and Technology K–6 · Year 3

   Cooling curve: how fast a cup of warm water loses heat

   A warm object loses heat to cooler surroundings, quickly at first and more slowly as the temperatures get closer, and a lid or insulation slows the loss.

   Practical, model not builtLow risk

6. Science and Technology K–6 · Year 3

   Freezing water: it takes up more room as ice

   Removing heat turns liquid water into solid ice, and unlike most substances water expands when it freezes, which can be measured as a rise of about 9 percent in volume.

   PracticalLow risk

7. Science and Technology K–6 · Year 3

   Melting ice: the thermometer stops at zero

   Adding heat to ice makes it melt, but while ice and water are together the temperature stays at 0 degrees Celsius because the energy is being used to change state, not to warm the water.

   Practical, model not builtLow risk

8. Science and Technology K–6 · Year 3

   Solid or liquid? Testing properties, then meeting cornflour slime

   Solids keep their shape and liquids take the shape of their container and can be poured, and testing those properties on a cornflour and water mixture shows why scientists test rather than assume.

   PracticalLow risk

9. Science and Technology K–6 · Year 5

   Balloon on a bottle: air expands when it is warmed

   Warming a gas makes its particles move faster and spread out, so air in a bottle expands and inflates a balloon, and cooling reverses it, without any air being added.

   Practical, model not builtLow risk

10. Science and Technology K–6 · Year 5

    Food dye in hot and cold water: particles move faster when warm

    Particles in a liquid are always moving and move faster when warmer, so a drop of dye spreads through warm water sooner than through cold, though the fast swirling seen in a glass is mostly currents and true particle spreading is slow.

    Practical, model not builtLow risk

11. Science and Technology K–6 · Year 5

    Squash the syringe: gases compress, liquids do not

    Gas particles are far apart with empty space between them, so a sealed syringe of air can be pushed to half its volume, while water particles are already touching and the plunger will not move.

    Practical, model not builtLow risk

12. Science and Technology K–6 · Year 6

    Dissolving and getting it back: separating sand and salt

    Dissolving is a reversible change: salt dissolved in water passes through a filter that stops sand and is recovered unchanged when the water evaporates, with its mass back on the balance.

    PracticalLow risk

13. Science and Technology K–6 · Year 6

    Fizz in a sealed bottle: a new substance, and no mass lost

    Bicarbonate of soda and vinegar react to make new substances, including carbon dioxide gas, an irreversible change; in a sealed bottle the total mass stays the same, and it falls only when the gas is let out.

    Practical, model not builtMedium risk

14. Science and Technology K–6 · Year 6

    Heat and food: which changes can be undone?

    Heating melts chocolate and butter, changes that reverse on cooling, but sets egg white and browns bread, changes that make new substances and cannot be undone.

    Teacher-led practicalPracticalMedium risk

15. Science and Technology K–6 · Year 6

    Lemon cells: chemical energy into electrical energy

    Two different metals in an acidic fruit make a cell that transforms chemical energy into electrical energy; one cell gives less than 1 V and a tiny current, so cells are joined in series to light an LED.

    PracticalLow risk

16. Science and Technology K–6 · Year 6

    Rusting steel wool: what it needs and how much air it uses

    Rusting is an irreversible change in which iron combines with oxygen and water to form a new substance, so steel wool rusts only when both are present, rusts faster with salt, and uses up the oxygen in the air around it.

    PracticalLow risk