Problem Solvers

Clean up the beach

Clean up the beach

Get your class thinking creatively about how to clean up a beach!

Activity overview

30 mins+
Ages 9 – 11

Science topics:

Materials , Climate challenge

You will need:

MODELLED DIRTY BEACH (could be pre-prepared or you could create the modelled dirty beach by adding each item and discussing where it comes from): Sand, salt, paper clips (representing ring pulls and cans), and clean plastic waste (or plastic beads if preferred).  EQUIPMENT: Beakers, funnels, sieves, filter paper, magnets.

Sometimes you have to solve a problem on the spot. Explain that today the class will need to clean a container of sand using just the materials provided.

Run the activity

In this activity, the italic sections marked with the polar bear explain how you can link the children's learning to the Climate Challenge, and support the children to take positive action.

Introduction: Explain that beaches around the world are becoming more and more polluted. Today the class will need to clean a container of ‘dirty beach’ using just the materials provided.  

1. Working as a team, they will have 2 minutes to look at the materials and plan a method to separate the sand from the other items in the mixture.  

2. Improving: After 2 minutes, discuss your plan with another group. Feedback your ideas to each other making sure you balance positive remarks and suggestions for improvement. What have you learned from swapping ideas? How can both groups improve their plans? 

3. Allow the children to use their method to separate the sand from the mixture. 

Background science

When teaching children about the Climate Challenge, it is important that we give them the facts (age appropriately and sensitively). During your discussion, allow time for children to express their thoughts and feelings and have them validated.

Some mixtures may be harder to separate than others but mixing and dissolving are always reversible changes. There are many different methods to separate mixtures. These include picking out large solids by hand, sieving, filtering, using magnets, using differences in density and using currents of air.  Solutions cannot be separated by normal sieves or filters. Dissolved materials can pass through the tiny holes in filter paper. One method of separating solutions is distillation. The water is heated until it evaporates (turns into a gas). The solute is left behind. The water vapour can be collected and cooled, so it changes back into liquid water. This distillation process is shown in the BBC video clip here.  

The British Science Association has revealed that the five most common items found on UK beaches include plastic food wrappers, plastic bags and plastic bottles. Much of this (estimates are about 80%) has come from the land. Plastic litter gets blown into rivers and drains and gets carried out to sea. Plastic is dangerous for marine wildlife. Over 700 species have been found to have eaten plastic or been entangled in it. Discuss whether it is better to clean up beaches or prevent them from getting polluted in the first place. Talk about what your class could do to help reduce the amount of plastic pollution in the world’s oceans. 

Take it further

After giving children the information they need about Climate Challenge issues, give them time to express how they feel, empathising with them and validating their feelings before taking it further.  


If they haven’t already noticed the grains of salt mixed with the sand, challenge your class to separate the sand and salt too. You could ask them to think about which of the two substances dissolves in water and whether or not a solution can be separated by filtering. Guidance lesson available here.   


Watch Plastic Soup’s video to find out more about the problems with plastic pollution and what can be done to prevent it. Watch this Wildlife Watch video about cleaning up your patch- whether it is the beach or the school playing field. 

Discuss with the children what could be done to help and if there is a positive action they can take themselves. Explain that when lots of people carry out small positive changes, it can have a big impact overall.

Positive action

If you live near a beach, you can organise or join in with a beach clean yourselves. The Marine Conservation Society offers excellent guidance. If you don’t live near a beach, then perhaps you could organise a litter pick to clean up your local environment? Keep Britain Tidy offer some good advice to help you prepare for a safe litter pick. For more ideas on small positive steps to help the planet, read our article on The Climate Challenge.

Image credit: Africa Studio via Shutterstock