California Grade 5 Science

Keep matter movement separate from energy transfer

Build a garden food-web model, trace matter through organisms and the environment, and distinguish energy from the sun. Includes California Grade 5 references.

Curriculum source: California’s Grade 5 science document, linked by the state science standards directory. The state’s current directory links the adopted California Next Generation Science Standards. Read the full performance expectations, examples, and boundaries alongside this selected activity.

A garden model needs more than a plant-to-animal arrow

A classroom model includes a lettuce plant, a snail that eats lettuce, a bird that eats the snail, and decomposers acting on dead material and waste. Add air, water, and materials in the soil as parts of the environment. Then add sunlight as the plant’s energy input. This is a simplified example, not a survey of every species or feeding relationship in a particular garden.

Explain the result

Food moves matter from the plant to the snail and then to the bird. Dead material and waste provide matter that decomposers break down, and materials return to the environment. Plants use matter from air and water to make food, with sunlight providing energy for the process; they do not obtain most of their food by eating soil. The energy in the animals’ food traces back through the plant to sunlight. Matter and energy are related in the model, but the arrows should not imply that sunlight turns into soil or that energy cycles in exactly the same way as matter.

What to check in the explanation

A line from decomposers back to the plant needs an explanation of the environment, not the statement “plants eat decomposers.” Avoid drawing an energy arrow from the soil as the plant’s primary energy source. The model here highlights one feeding pathway and decomposer connections; a complete classroom food web would add other organisms and relationships, and it would still be a model with limits.

Plan the next activity

1. Draw a feeding pathway and label arrows to show the direction matter moves when something is eaten.
2. Add dead material, waste, decomposers, and the environment so matter is accounted for beyond the feeding pathway.
3. Use a separate label or arrow for sunlight energy, then explain why it is different from a matter arrow.

Ask what would change in the model if fewer snails were present. List possible effects and explain which ones depend on feeding relationships the model does not yet include. Return to the diagram to revise an unclear arrow. Grade 5 explanations can use organisms and environmental materials without a molecular account of photosynthesis.