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Important update from TheSchoolRun

For the past 13 years, TheSchoolRun has been run by a small team of mums working from home, dedicated to providing quality educational resources to primary school parents. Unfortunately, rising supplier costs and falling revenue have made it impossible for us to continue operating, and we’ve had to make the difficult decision to close. The good news: We’ve arranged for another educational provider to take over many of our resources. These will be hosted on a new portal, where the content will be updated and expanded to support your child’s learning.

What this means for subscribers:

  • Your subscription is still active, and for now, you can keep using the website as normal — just log in with your usual details to access all our articles and resources*.
  • In a few months, all resources will move to the new portal. You’ll continue to have access there until your subscription ends. We’ll send you full details nearer the time.
  • As a thank you for your support, we’ll also be sending you 16 primary school eBooks (worth £108.84) to download and keep.

A few changes to be aware of:

  • The Learning Journey weekly email has ended, but your child’s plan will still be updated on your dashboard each Monday. Just log in to see the recommended worksheets.
  • The 11+ weekly emails have now ended. We sent you all the remaining emails in the series at the end of March — please check your inbox (and spam folder) if you haven’t seen them. You can also follow the full programme here: 11+ Learning Journey.

If you have any questions, please contact us at enquiries@theschoolrun.com. Thank you for being part of our journey it’s been a privilege to support your family’s learning.

*If you need to reset your password, it will still work as usual. Please check your spam folder if the reset email doesn’t appear in your inbox.

What are states of matter?

What are states of matter?
Matter makes up our physical universe. In primary school children learn about the matter on Earth, which exists in one of three main states: solid, liquid or gas. We explain what your child is taught about states of matter in KS2 science.

What is matter? What are states of matter?

Matter makes up our planet and the whole universe. On Earth, all matter exists in one of three main states: solid, liquid or gas.

A solid can hold its shape (for example, water in solid form is ice).

A liquid like water forms a pool: it flows or runs but it can't be stretched or squeezed.

A gas can flow, expand and be squeezed; if it is in an unsealed container it escapes (water in gas form is steam).

Depending on its temperature, matter can change state; heating, cooling, evaporating and condensation are ways in which a material changes state.

The diagram below shows that:
 

  • Melting is the process of changing a solid into a liquid.
  • Evaporation is the process of changing a liquid into a gas.
  • Condensation is the process of changing a gas into a liquid.
  • Freezing is the process of changing a liquid into a solid.

What do children learn about states of matter in primary school?

In KS2 children learn about types of solids, liquids and gases, how temperature and pressure affect substances in different states and how matter changes state.

A reversible change is a change that can be changed back again. For example, if an ice-cube is melted it becomes water but we can freeze it again to become an ice-cube so it can return to its original state. Melting and heating are examples of reversible changes.

An irreversible change is a change that cannot be changed back again. For example, if a cake mixture is baked it becomes a cake and we cannot turn it back into a mixture. The change is irreversible because a chemical reaction has taken place. Burning or mixing a liquid with bicarbonate of soda are examples of irreversible changes. 

They also learn that:
 

  • Filtering and sieving are methods of separating mixtures of solids and liquids.
  • Dissolving is a way of mixing a solid and a liquid. When a solid dissolves in a liquid it creates a solution, for example when sugar dissolves in water.

When are children taught about states of matter in primary school?

In Year 4 children will learn:
 

  • To group or sort materials into solids, liquids and gases
  • To observe that some materials change state when heated or cooled
  • To understand and use the terms evaporation and condensation
  • To describe solids, liquids and gases

In Year 5 children will learn:
 

  • That some changes are irreversible
  • That some materials dissolve in liquids to make a solution
  • To investigate how solutions can be separated using filtering and sieving
  • To identify some reversible and irreversible changes

How are children taught about states of matter in the classroom?

Children may sort materials or pictures of materials into solids, liquids and gases.

They may also carry out some practical investigations:

  • Children may explore reversible changes such as heating and cooling by making chocolate crispy cakes or ice-lollies
  • Children may explore irreversible changes by making a bicarbonate of soda volcano, baking cakes or making toast
  • Children will investigate how to separate solutions using sieving and filtering

Books about states of matter for children

     

States-of-matter activities for at-home learning:

  • Melt chocolate and butter to make chocolate crispy cakes
  • Make ice-cubes or ice-lollies or home-made ice-cream
  • Make a cake or bake bread to observe the irreversible change
  • Observe how clothes dry on the line in the sun.
  • Mix bicarbonate of soda with vinegar to observe what happens
  • Use sieves and filter paper (or kitchen roll) to separate solutions of sugar and water, salt and water or soil and water.