Grades K–2 · Semester 4 · 47 readings
Discover living and designed systems
Begin with signals we can notice. Follow the connected explanations through small parts in familiar objects, keeping each small group together and taking time to understand its illustrations.
Start reading →One possible pace is 2–3 explanations a week over 16 weeks. Keep each small unit together, revisit its pictures and allow more time whenever an idea needs it.
Unit 1Signals we can notice4 readings ⌄
A compass, a remote control, a sound groove and delayed thunder make different hidden processes noticeable.
Unit 2Structures and routes4 readings ⌄
Arches and braces help structures hold their shape. A tower and movable rails guide water and trains.
Unit 3Small parts at work4 readings ⌄
A lens, a turning vane, a rolling ball and bent metal legs make four useful objects work.
- How does a magnifying glass make small things look bigger?Everyday Life
- How does a weather vane show where wind comes from?Everyday Life
- How does a ballpoint pen leave a line?Everyday Life
- How does a stapler hold pages together?Machines
Unit 4Things that turn and move4 readings ⌄
A swiveling wheel, a spinning seed, a ringing bell and a rolling seal each turn movement into a different result.
Unit 5Small changes we can notice4 readings ⌄
Cool grass, a bubbling mixture, an eraser and a rolling pill bug reveal changes through familiar observations.
- How can grass become wet when no rain has fallen?Earth & Space
- Where do the bubbles come from when baking soda meets vinegar?Materials & Matter
- How does an eraser lift a pencil mark?Everyday Life
- How can a pill bug roll into a ball?Organisms
Unit 6Shapes, balance and messages4 readings ⌄
A round cover, a hanging mobile, signal flags and an undo button have different ways of making an arrangement useful.
Unit 7Shapes in action3 readings ⌄
A duck’s foot, a pencil sharpener and pairs of objects show how a familiar arrangement changes what happens.
Unit 8Surfaces and spaces3 readings ⌄
Frost, sticky tape and spaces between written words reveal three different reasons a small detail matters.
- How can tiny ice feathers grow on a cold surface?Earth & Space
- Why does sticky tape stay on a page?Everyday Life
- Why are there little spaces between words?Language
Unit 9Body parts that help us every day4 readings ⌄
Follow a blink, a supporting skeleton, a smell and a taste through simple pictures of the parts involved.
Unit 10The body at play2 readings ⌄
Follow everyday experiences into the hidden processes that make them possible.
- Why is standing on one foot wobbly?Organisms
- Why do you get warm when you play?Organisms
Unit 11Things that fold and fasten2 readings ⌄
An umbrella and a button use familiar moving parts and openings to do useful jobs.
Unit 12Body parts doing everyday jobs5 readings ⌄
Saliva, chewing teeth, hair, changing teeth and tear drainage reveal different jobs performed by familiar body parts.
Unit 13Small parts in familiar objects4 readings ⌄
Clips, safety pins, sliding drawers and a food processor use different shapes to hold, guide or change something.