States of matter (Y4)
States of matter is where children start explaining what they can see with something they can’t: particles. From solids, liquids and gases to melting, freezing and the water cycle, here’s what the Year 4 curriculum expects and where to find lessons and resources to teach it.
What children learn about states of matter in Year 4
What the national curriculum expects
States of matter is taught in Year 4. Pupils should compare and group materials according to whether they are solids, liquids or gases. They should observe that some materials change state when heated or cooled, and measure or research the temperature at which this happens in degrees Celsius. They should also identify the part played by evaporation and condensation in the water cycle, and associate the rate of evaporation with temperature.
Key knowledge and concepts
Within this topic, children build knowledge across the three states and how materials move between them:
Solids, liquids and gases
Grouping materials by their state, and what defines each one
Particle theory
The idea that explains why materials behave as they do
Change of state
How heating and cooling move a material between states
Melting and freezing
What happens at the melting point, and how to investigate it
Evaporation and condensation
The two processes at the heart of the water cycle
The water cycle
How water moves between the ground, the air and back again
Measuring temperature
Using thermometers and recording in degrees Celsius
Investigating materials
Fair tests, line graphs and recording results
Where this topic sits within KS2
States of matter is taught in Year 4, alongside Living things, Animals including humans, Sound and Electricity. It builds on the KS1 work on everyday materials, and feeds into the Year 5 topic Properties and changes of materials.
How to access this topic
States of matter doesn’t sit on its own in the curriculum. The Cornerstones science curriculum is fully sequenced from EYFS through Year 1 to Year 6, so you can see what comes before, what follows and how the whole picture fits together. We’ve done the thinking, so your planning time goes into teaching, not sequencing.
Full curriculum
Subject curriculum
Quick Teach Individual lessons and resources for supplementing what you already teach.
Ready to bring the wider curriculum to life?
See how the full Cornerstones Science Curriculum sequences topics like this one across every year group.
