Great question! Understanding advertisements is part of what we call Media Literacy. To find great information, videos and website links on Media Literacy, check out our 7-12 English Guides in the "I want to know about" box on the Virtual Learning Commons (VLC). http://vlc.ucdsb.ca/content.php?pid=360751.
There is a guide for each grade and each guide has a separate section called 'Media Literacy'.
The grade 11 English guide has an article on media issues with a section on marketing and consumerism. It is in the Media Literacy box. Check it out here:
http://vlc.ucdsb.ca/content.php?pid=326144&sid=3153269
The Media Awareness Network website can be found in the guides, but here is a direct link if you want to go there first to read their articles on consumerism, and check out their resources: http://mediasmarts.ca/marketing-consumerism