My dynamic geometry sketches site at http://math.kennesaw.edu/~mdevilli/JavaGSPLinks.htm
has been updated with the De Villiers Points of a Triangle and a Locus Problem, as well as some new dynamic Student Explorations like "Transformations of Figures & Graphs" under the link Student Explorations. The latter include dynamic translations, reflections, stretches, and enlargements of graphs, etc. Go directly to http://math.kennesaw.edu/~mdevilli/graphtransform.html 

Learners and teachers are likely to get useful ideas.

Michael de Villiers