3-LS4-4: Judging Solutions When a Habitat Changes
Also called NGSS 3-LS4-4 · Topic: Interdependent Relationships in Ecosystems: Environmental Impacts on Organisms · Life Science
The Official Wording
Make a claim about the merit of a solution to a problem caused when the environment changes and the types of plants and animals that live there may change.
Clarification statement: Examples of environmental changes could include changes in land characteristics, water distribution, temperature, food, and other organisms.
Assessment boundary: Assessment is limited to a single environmental change. Assessment does not include the greenhouse effect or climate change.
NGSS Lead States, 2013 · Read it on nextgenscience.org · checked October 15, 2026
What 3-LS4-4 Means in Plain English
Third graders look at a problem caused when a habitat changes, like trees being cut down or a pond drying up, and decide how well a proposed fix would work. They back their claim with evidence about which living things the change affects and what they need.
Students look at one change at a time, such as less water, a new road or a lost food source, and climate change is left for later grades. This builds on 3-LS4-3 and leads to MS-LS2-5, which compares ways to protect ecosystems.
3-LS4-4 I Can Statements
- I can explain how a habitat change affects living things.
- I can judge how well a solution fixes the problem.
- I can support my claim with evidence and criteria.
3-LS4-4 Worked Example
A design test of model nest boxes for bluebirds after the old dead trees in a park were cleared.
Which milk carton nest box would best replace the tree holes the bluebirds lost?
Set It Up: Two cleaned half-gallon milk cartons cut into model nest boxes, a ruler, a watering can, and a criteria chart.
- State the problem: bluebirds nest in holes in dead trees, and the park cleared those trees.Fewer nesting holes
- List criteria: the hole fits a bluebird but blocks bigger birds like starlings, and the inside stays dry.Hole about 3.8 cm wide, dry floor
- Measure the entrance hole on each design.Box A: 3.8 cm. Box B: 6 cm
- Sprinkle a cup of water over each roof from the watering can and check the floor.Box A: dry. Box B: wet floor
- Score each box against the criteria.Box A meets both
Box A had the right size hole and stayed dry, so the class claimed it was the better replacement for the lost tree holes.
Why it works: When a change removes something a living thing needs, a good solution supplies that need in a way that fits the animal's size and habits.
Common Mistakes with 3-LS4-4
Judging a solution by how it looks
“Box B is better because it is painted.”
Try this: Score each design only against the criteria, like hole size and staying dry, then decide which one meets the most.
Forgetting what the animal needs
Cutting a big hole so more birds can fit
Try this: Start from the animal's needs. A hole sized for bluebirds keeps out bigger birds that would take over the box.
Claiming a fix solves everything
“Now all the park animals are fine.”
Try this: Name exactly which living things the solution helps. Nest boxes help hole-nesting birds but do nothing for animals that needed the trees for food.
Where 3-LS4-4 Fits
Practice 3-LS4-4
Quick Check
- Why do bluebirds need help when old dead trees are cut down?
- What makes a solution to a habitat problem a good one?
- A pond dries up. Name a living thing that would struggle.