practicalaction.org/floatinggardenchallenge Briefly explain that this is a challenge put together by an organisation called Practical Action; a charity who work with poor people all over the world, using technology to help them lift themselves out of poverty. practicalaction.org/floatinggardenchallenge

What problems are caused by climate change? Look at the pictures given to you by your teacher What is happening? Where do you think it is happening? What long term problems may result from events like this? Is there anything that links all the pictures? ACTIVITY: Sort your pictures into two groups. You decide how…. Divide students into groups, give each group a set of pictures and encourage them to discuss. Climate change is making both flooding and drought more of a problem throughout the world.

Flooding and drought You may have divided your pictures into different groups: Flooding and drought, or Effecting the UK and other countries. Either way is correct  Flooding and drought are caused by changing weather patterns and are having devastating impacts in the UK and around the world. Some of the students will have divided pictures into groups – drought and flooding. Discuss how these extremes are both being made worse as a result of climate change.

Impacts of changing climates Practical Action works with communities living in Bangladesh, who experience some of the worst effects of climate change. Floods affect over 1 million people in Bangladesh and last longer each year. During the monsoon season, many families lose their crops and the vegetables they were growing to feed their families. Explain the challenge: you may like to look at the geography of Bangladesh and get students to think about why Bangladesh is more prone to flooding than other countries. It is important that they understand flooding has always been a problem but climate change is making it worse.

Your Challenge The problem: The land where crops used to grow now gets regularly flooded The challenge: Design and build a model of a structure that farmers could grow their crops on even when it floods There are teacher’s notes to support you to prepare and run the challenge, available on the website. For secondary age students, if you would like your students to take part in the CREST Award scheme, worksheets are provided. They will need to produce three different designs and their work will need to be reviewed by yourself or the CREST Local Coordinator. If you are new to CREST please do contact a coordinator before you start. They will support you through the challenge and can help you find mentors. For more information visit britishscienceassociation.org/crest or email crest@britishscienceassociation.org. For primary age students you could adapt for a CREST Superstars award by simplifying to designing one floating garden then building it. You could also give students a set of materials to choose from with two or three variables e.g. buoyancy.

What should you consider? For crops to grow on flooded land they need to be planted on a raft-like structure, or ‘floating garden’, so make sure your model floats. You can use any materials provided by your teacher. Think about making your raft stable. The top of your model should be fairly flat so you could grow your own garden on top of it. Your model must not be wider or longer than 23 x 30 cm, but can be as deep as you like. The winning group will be the one whose raft holds the most weight before it sinks. Provide a range of material for students to make their rafts with e.g. plastic drinks bottles, K’Nex, doweling, straws, corks, plastic sheets, plastic bags, sellotape, string, yogurt pots, bubble wrap, plastic milk bottles, lollypop sticks. Each group will also need a washing up bowl with about 10cm of water in the bottom. Weights will be needed to test the raft. Expect rafts to hold up to 5 KG.

A solution developed in Bangladesh… Practical Action works with people to develop sustainable technologies and skills that enable people to have a decent quality of life – we call this TECHNOLOGY JUSTICE. In Bangladesh, Practical Action worked with farmers to develop ‘floating gardens’, a technology that uses locally available materials to grow vegetables even during the floods. For further information on the technical construction of a floating garden and its use in Bangladesh a technical brief is available at practicalaction.org/floating-gardens.

How are floating gardens made? The rafts are approximately 8 metres long and 1 metre wide. They are made up of layers of water hyacinth, bamboo, cow dung and compost. The crops are then grown on the top layer of soil. The garden floats to the top of the water during the rainy season and returns to ground level when the floods subside. For further information on the technical construction of a floating garden and its use in Bangladesh a technical brief is available at practicalaction.org/floating-gardens.

Are the gardens making a difference? Many families are benefiting from their floating gardens as they’re able to grow vegetables such as okra and leafy vegetables throughout the year. Some are even keeping their goats and chickens on them! During harvesting, the rafts can be accessed by foot or by raft or boat if the water is very deep. A more detailed case study of Rahima and how her family has benefited from their floating garden is available at practicalaction.org/floating-gardens

Other things to think about Why are hyacinth roots and bamboo used instead of man made materials? What do you think happens to the ‘raft’ once the crops have been harvested? Families who grow crops also keep livestock such as goats. What do you think happens during the floods? Can you guess what Practical Actions’ solution has been? Do you think floating gardens can be used elsewhere in the world? To find out more go to practicalaction.org/floating-gardens Floating gardens are an excellent example of sustainable farming. The materials used are locally available. The old rafts are used as fertilizer for the next crop. Go to practicalaction.org/floating-gardens to find out more. We have also encouraged farmers to keep ducks instead of goats for one simple reason – ducks float!!

What can you do next? Grow some food on your floating garden! Place damp blotting paper and a bit of soil on top of your garden. Then sprinkle a few cress or lettuce seeds on top and watch your garden grow. Scale Up – develop a real floating garden for use on a pond. There are a number of other activities your students can get involved in following the challenge. They are freely available at practicalaction.org/stem

Taking your ideas further… If you’ve enjoyed making your floating garden – you might want to try some of Practical Action’s other challenges. CREST global challenges Squashed tomato challenge Wind power Small is… challenge practicalaction.org/stem There are a number of activities your students can get involved in following the challenge. They are freely available at practicalaction.org/stem There are a number of activities your students can get involved in following the challenge.

Thank you for taking part in the challenge Let us know how you got on with your floating garden by emailing your photos to schools@practicalaction.org.uk. We’ll add them to our website: practicalaction.org/schools