Waterfalls are also a feature of the upper course. Over time this leads to the formation of V-shaped valleys. As the valley deepens the sides become unstable and collapse. The river erodes downwards carving the valley floor. The water has enough energy to transport boulders and rocks in its swift current. As it moves over rocks, the water becomes turbulent and appears fast-flowing. In the upper course the river bed is narrow and rocky. Here, high levels of precipiation (rain and snow) combined with steep slopes and sparse vegetation result in water flowing overland. The source of a river is often in upland areas. Show pupils photographs illustrating the upper course. Reiterate that rivers can be divided into stages, the upper course, middle course and lower course. Locate the River Severn on Google Earth, or use an atlas. Pupils may notice that the mud flats which signify that the tide is out. These photographs show the River Severn in the upper course, middle course and at the lower course – where the Severn Estuary becomes tidal and eventually flows into the Bristol Channel. Explain that a river can take on different characteristics at different points in its course. What is the evidence that these bodies of water are rivers? (The photograph of the estuary could be thought of as coastal)Įstablish that the photographs are of the same river, the River Severn – the UK’s longest river. How does the water change? Is the water turbulent or calm?
Do not contextualise the photographs.Īsk pupils to identify enquiry questions: what, where, when, why, how. Each photograph shows the river at different points its course. To ensure prior knowledge of the water cycle go to Crickwebīegin the lesson by showing pupils photographs of the River Severn. To understand that the features of a river and the surrounding landscape change from source to mouth. The Factsheet, to accompany this lesson also explains some of the main points in more detail. The PowerPoint presentation follows the sequence of the lesson and contains the photographs and images that illustrate the main teaching points. Use the PowerPoint presentation in conjunction with the Lesson Plan.
Rivers, and the landscape that surrounds them, have different characteristics as they move from the upper course, into the middle and lower course.
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