Dollar Street shows photos of everyday things in homes (bed, toothbrushes, toilets etc) ranked by the income of the household. Pictures cover 50+ countries and show the fascinating ordinary lives of ordinary people.
In the classroom, they are really useful for showing inequality, both within and between countries, and the tool makes for a great conversation starter about the links between growth, material wealth and development.
The women behind the project has given a great TEDTalk: