This lesson is designed to help students gain knowledge in graphing a microset of data, then using the graphs to investigate trends in cloud coverage over a given locale. Students are provided content-related activities to enhance background knowledge in cloud types, and then are provided detailed instructions on how to download data from the MY NASA DATA Live Access Server (LAS) and to use Excel to graph the data. The graphs are then used to explore trends in cloud coverage over Toronto, Ontario, Canada for a given time period. The lesson provides detailed procedure, related links and sample graphs, follow-up questions and extensions, and Teacher Notes. Educational levels: General public