Describe how magma can be erupted place. Show them some smaller the idea that with extrusive to form volcanoes. crystals formed by heating a solution the larger magmas by Describe how igneous are formed. to evaporate it. Describe the crystals there measuring the Recall the names of some igneous and differences in the way they were was more time cooling rate of metamorphic rocks. prepared and ask students to suggest for particles to two beakers of Describe the textures and properties of why crystals of different sizes were join up. Use this hot water, one igneous and metamorphic rocks. obtained. opportunity to surrounded by Describe how metamorphic rocks are probe students’ sand formed. Exploring: Cooling curve understanding of (representing Explain how the size of crystals in Ask students to model the cooling what crystals are. rock) and one igneous rocks is evidence for the speed rates of intrusive and extrusive surrounded of cooling and describe some factors magmas by measuring the cooling Explaining: by air. that affect this. rate of two beakers of hot water, one Modelling Securing surrounded by sand (representing metamorphism Use crystal size to classify igneous rock) and one surrounded by air. Extend this to as intrusive and extrusive. model the Explain the variation in crystal size in Explaining: Modelling metamorphism deformation of an igneous intrusion, in terms of Model metamorphism by showing grains in the cooling rate. students unbaked cake mixture and a metamorphism of Exceeding baked cake, emphasising that there a sedimentary Compare the densities of igneous rocks have been no chemicals added in the rock and the and relate them to the minerals transformation of one to the other. alignment of contained in the rocks. platy minerals Plenary: Thinking about igneous and when mudstone metamorphic rocks or shale is Consider All Possibilities: A rock has converted to changed to a metamorphic rock. slate. (Possible answers: the original rock was buried by earth movements; some magma was forced into the crust near the original rock and heated it.) Lesson 8Hc: Weathering and erosion Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills
Describe how magma can be erupted to form volcanoes. Describe how igneous are formed. Recall the names of some igneous and metamorphic rocks. Describe the textures and properties of igneous and metamorphic rocks. Describe how metamorphic rocks are formed. Explain how the size of crystals in igneous rocks is evidence for the speed of cooling and describe some factors that affect this. Securing Use crystal size to classify igneous as intrusive and extrusive. Explain the variation in crystal size in an igneous intrusion, in terms of cooling rate. Exceeding Compare the densities of igneous rocks and relate them to the minerals contained in the rocks. place. Show them some smaller crystals formed by heating a solution to evaporate it. Describe the differences in the way they were prepared and ask students to suggest why crystals of different sizes were obtained. Exploring: Cooling curve Ask students to model the cooling rates of intrusive and extrusive magmas by measuring the cooling rate of two beakers of hot water, one surrounded by sand (representing rock) and one surrounded by air. Explaining: Modelling metamorphism Model metamorphism by showing students unbaked cake mixture and a baked cake, emphasising that there have been no chemicals added in the transformation of one to the other. Plenary: Thinking about igneous and metamorphic rocks Consider All Possibilities: A rock has changed to a metamorphic rock. (Possible answers: the original rock was buried by earth movements; some magma was forced into the crust near the original rock and heated it.) the idea that with the larger crystals there was more time for particles to join up. Use this opportunity to probe students’ understanding of what crystals are. Explaining: Modelling metamorphism Extend this to model the deformation of grains in the metamorphism of a sedimentary rock and the alignment of platy minerals when mudstone or shale is converted to slate. extrusive magmas by measuring the cooling rate of two beakers of hot water, one surrounded by sand (representing rock) and one surrounded by air. Lesson 8Hc: Weathering and erosion Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills