In France, project activities figure predominantly in technology education. The general idea behind learning based on project activity is to allow the pupil to get involved in the activity in question, with the pupil tackling real situations rather than ones of an abstract nature. But too often, we notice that the pedagogical strategies used by teachers in project activities are not particularly effective from a learning point of view. What must be done in order to render project work in technology teaching genuinely effective? In this article, we make the following suggestion: if specific help, based on the pupil's level of understanding of the activity relating to technologically based problem solving in project work, is made available by the teacher, then project activity can become much more effective from a learning point of view. By using situations highlighting project activities in the technology teaching domain, we analyse the knowledge used by pupils. We then present the specific help used by the teacher as well as the resulting effects upon student activity. We highlight the fact that if specific help conceived as a result of analysing student activity is put in place, the pupil learns more effectually.