In this activity students complete missing notes that the teacher provides through a PowerPoint presentation. They are notes about Air pollution covering the definition of pollution, primary and secondary pollutants, smog, acid rain, CFCs, and short and long term effects of pollution. I read through each sentence as students fill in the missing information and add more information to extend the ideas. It's a good way to keep student engaged on what you are saying because they are waiting for the missing information.
The last slide can be used as an extension activity example in which students can create a "Stop Pollution Poster." They wrote in large letters any message saying how pollution is bad (e.g. Stop Pollution) and then drew four pictures showing how to stop or minimize pollution.