This final article focuses in particular on the engagement of year 8 students who were taught trigonometry using dynamic geometry software ("Geometer's SketchPad"), as outlined in "MT214" and with resources from the ATM website. The project was implemented in three different classrooms in two different, multiracial, comprehensive and oversubscribed London schools. The selected groups comprised thirty Year 8 students including some with special needs. Both schools place students in different sets according to their ability. Each teacher prepared a sequence of four lessons. The topic was introduced using a combination of the two main methods for introducing trigonometry: (1) the ratio method; and (2) the unit circle method. In this article, the authors evaluate the work they undertook using "Geometer's SketchPad". (Contains 2 figures.)