Follow a question from one subject into another. Choose a grade collection, then a theme. Each route connects eight complete, illustrated explanations from the wider collection.
Grades K–2
Notice a change and follow what causes it.
Begin with things you can see, hear and recognize. Simple connections link movement, materials, living things and shared routines.
Grades 3–5
Discover the parts and transfers that are harder to see.
Look inside familiar objects and follow signals, materials and living processes. Pictures and records reveal clues about hidden connections.
Grades 6–8
Connect interacting parts, feedback and evidence.
Follow processes through bodies, machines, environments and communities. Compare what a system does with the evidence used to explain it.
Grades 9–12
Use models and measurements to explain complex relationships.
Connect physical laws, molecular structures, information and human choices. Each route makes the assumptions and limits of its explanations visible.
These are guided connections through the collection. Each explanation keeps its own age placement and mechanism. The semester paths provide a longer sequence through all 1221 topics.