Formation of the early atmosphere

This lesson has been designed to enable students to recognise the key stages in the formation of the early atmosphere and to also show how today’s atmosphere was formed. The lesson has been primarily designed for GCSE students but is suitable for higher ability younger students who perhaps are studying the Earth and its formation.

The lesson begins by checking that the students know the percentages of the different gases found in the modern day atmosphere. Some time is taken to check on their mathematical skills by challenging them to produce a pie chart to represent these different percentages. Students are then asked to predict how they think the percentage of oxygen, carbon dioxide and water vapour would have differed from now to the early atmosphere. The key steps in the formation are then introduced and critical points discussed. Students will learn about the volcanic activity, formation of the oceans and photosynthesis as crucial points in the change to the percentages of those three gases. A number of progress checks are written into the lesson, which check knowledge from this lesson and related topics such as the reaction of acids and gases.