Plant families are the level of the taxonomic hierarchy that many biologists use to organise their understanding of plant diversity. Consequently, from many perspectives, it is very useful to be able to recognise the major plant families "on sight". To this end numerous books and web sites have described and illustrated plant families, but few resources are available for students to test their recognition skills. The application described in this paper features an illustrated tutorial for 11 of the largest plant families in Australia (they cover over 50% of Australia's plant species), augmented with a series of interactive tests. The tests are organised in five groups of 20 high quality images. Each image is supplemented with optional hints to the main features of flower structure and an optional reminder of the family names. The web site is one part of an integrated series of activities to assist students to recognise some of the most important plant families and thus master a very useful practical skill. (Contains 1 table and 3 figures.)