Rocks to Stars: Earth and Space

You need: 6–10 rock samples (pumice, basalt, greywacke, granite, sandstone, limestone, quartz, coal) · a hand lens · an unglazed white tile · a 5-cent coin and a steel nail · vinegar and a dropper · a bowl of water · goggles

1. Look at each rock with the hand lens. Can you see crystals, grains, layers or holes?
2. Rub the rock on the white tile. What colour is the streak?
3. Try scratching it with your fingernail, then the coin, then the nail. Which one leaves a mark?
4. Put one drop of vinegar on a corner. Does it fizz? (Fizzing shows calcium carbonate, found in limestone and shells.)
5. Drop it gently into water. Does it float?
6. Record each result in your rock passport and name the rock using the class chart.

How you'll know: You can name at least four rocks from your test results, and explain why limestone fizzes and pumice floats.

Safety: Wear goggles when scratching and dropping vinegar. Scratch away from your body. Wash hands after handling coal.

Go further: Use your results to make a hardness order from softest to hardest and compare it with the Mohs scale.

You need: a clear jar with a lid · a handful each of gravel, sand and garden soil · water · a timer · a notebook

1. Put the gravel, sand and soil in the jar and fill it three-quarters with water.
2. Screw the lid on tight and shake for 30 seconds.
3. Predict the order the layers will settle in and draw it.
4. Leave the jar still. Draw what you see after 1 minute, 10 minutes and the next day.
5. Compare with a photo of a cliff or road cutting. Which layers are oldest?

How you'll know: Heavy gravel settles first at the bottom and fine mud last at the top. You can use this to explain why the lowest layers in a cliff are usually the oldest.

Safety: Glass jars can break: hold with two hands and shake over a table. Wash hands after handling soil.

Go further: Add a small shell before you shake. Where does it end up, and how could it become a fossil?

You need: shells, leaves or a plastic toy animal · salt dough or modelling clay · plaster of Paris and water · a paper cup · petroleum jelly

1. Flatten the dough into a thick disc in the bottom of the cup.
2. Wipe the shell with a little petroleum jelly and press it firmly into the dough. Lift it out carefully. This is a mould fossil.
3. Mix plaster with water until it is like thick cream and pour it into the mould.
4. Leave it overnight, then peel away the cup and dough. You now have a cast fossil.
5. Write the steps a real shell in the Whanganui sea would go through to become part of the cliff.

How you'll know: You can explain the difference between a mould and a cast, and describe how sediment, time and minerals turn a buried shell into a fossil.

Safety: Wear goggles and gloves when mixing plaster, do not breathe the dust, and never put your hand in setting plaster: it gets hot. Do not pour plaster down the sink.

Go further: Swap fossils with another group and write an identification card for theirs, as a museum would.

You need: a clipboard and checklist · a camera or tablet · a magnet · a map of the school

1. Walk a planned route with an adult. Find 10 things made from Earth materials: concrete, bricks, gravel, glass, steel, copper pipes, roofing iron, a stone wall.
2. Photograph each one and test with the magnet: is there iron or steel in it?
3. Record why you think that material was chosen (strong, light, does not rust, cheap, looks good).
4. Back in class, find out which rock or deposit each came from (limestone for cement, sand for glass, ironsand for steel).
5. Draw a 'from rock to road' flow chart for one material.

How you'll know: You have 10 materials, each linked to a source rock and a reason for its use based on its properties.

Safety: Stay with your group and the adult. Look, do not climb. Keep away from building sites and the caretaker's workshop unless invited.

Go further: Find out how much gravel and sand New Zealand uses each year, and where your region's nearest quarry is.

You need: a roll of toilet paper (at least 300 sheets) · 8 planet cards and a Sun card · a marker pen · the scale table · a long, clear space such as the field or a corridor

1. Use the scale: 1 sheet stands for about 15 million km.
2. Place the Sun card at the start of the roll.
3. Count out sheets and put each planet card down at its place: Mercury about 4 sheets, Earth 10, Mars 15, Jupiter 52, Saturn 95, Uranus 191, Neptune 300.
4. Walk from the Sun to Neptune. Stop at Earth and look back.
5. Write what surprised you, and why pictures of the Solar System are not to scale.

How you'll know: You can explain that the inner planets are crowded close to the Sun and the outer planets are enormously far away, using your scale model.

Safety: Outdoors: sunhat and sunscreen in summer. Pick up all the paper afterwards and recycle it.

Go further: Work out how far away the nearest star after the Sun would be on the same scale (about 40 trillion km). How many rolls would you need?

You need: a soft ball or beanbag tied to 1 m of string · two balls of different mass (a tennis ball and a heavier ball) · a tape measure · an open space

1. Drop the two balls from the same height at the same time. Which lands first? Repeat three times.
2. Swing the ball on the string gently in a horizontal circle, low to the ground.
3. Let go of the string. Watch which way the ball flies.
4. Discuss: what did the string do? What does gravity do for the Moon?
5. Draw the Moon's orbit with an arrow showing the pull of gravity towards the Earth.

How you'll know: Both balls land together. The string pulls the ball towards the centre; when it is let go, the ball flies off in a straight line. Gravity is the invisible 'string' holding the Moon in orbit.

Safety: Swing the ball low and slowly, in a clear space, well away from other people and windows.

Go further: Use the PhET Gravity and Orbits simulation to find out what happens to the Moon's orbit if you turn Earth's gravity off.

You need: a lamp with the shade removed · a polystyrene or tennis ball on a pencil or skewer · a darkened room · a phase-drawing sheet

1. Stand in the middle of the room facing the lamp. Your head is the Earth.
2. Hold the ball at arm's length, a little above your head, between you and the lamp. How much of the lit side can you see?
3. Turn slowly to your left, keeping the ball in front of you. Stop every eighth of a turn and draw the lit shape you see.
4. Name each phase: new, crescent, first quarter, gibbous, full.
5. Explain in one sentence what causes the phases.

How you'll know: You have drawn a full cycle of phases and can explain that half the Moon is always lit by the Sun, and the phase depends on how much of that half faces us.

Safety: The bare bulb gets hot: do not touch it and keep cords taped down. Move slowly in the dark.

Go further: Find out how the maramataka names nights of the Moon and what some iwi use them to plan, such as planting or fishing.

You need: a printed star map or Stellarium Web on a device (set to night mode) · a red-light torch (red cellophane over a torch) · warm clothes · an adult

1. Check the weather and the rising time for Matariki in late June or July. Plan to go out about an hour before dawn with an adult.
2. Let your eyes get used to the dark for 10 minutes. Use only red light.
3. Look east. Find the three stars in a row called Tautoru (Orion's Belt).
4. Follow the line of Tautoru to the left to find the small, misty cluster of Matariki.
5. Record what you saw, how many stars you counted and how dark it was. If you watch in the evening instead, look for the Moon and a bright planet.

How you'll know: You have a sky-watch record with the date, time, direction and what you saw, and can explain how you found the cluster.

Safety: Always go with an adult and stay on your own property or a safe, familiar place. Never look at the Sun, even with sunglasses or through binoculars.

Go further: Compare the number of stars you counted with a class member in a darker or brighter place. What difference does light pollution make?