The work reported in this article is part of a wider project that aims to develop and implement a web-based, pan-European, in-service professional development platform for teachers to enhance their role in promoting education through science. This article aims to evaluate the implementation of the e-module on Assessment of Children's Learning in Primary Science, which was created at Bradford College (UK) and was adapted to be trialled by Portuguese science teachers. The article (i) evaluates the e-module in order to find facilities and constraints with a view to improving it in future versions; (ii) analyses participants' opinions concerning strategies explored, resources and their reflections on their learning; and (iii) discusses the impact of the training on teachers' professional development. Data was collected through three different online questionnaires: (i) at the start; (ii) at the end of the e-module; and (iii) one year after implementation of the e-module. The results indicate that the majority of the teachers recognised that the module promoted the development of new skills during the course, such as ICT skills, which have an impact on classroom practice and enhance their professional development both in the personal domain and in the domain of practice. It was also recognised by both trainees and tutors that the main advantage of using an e-learning platform was that it enabled an adjustment to individual needs taking into account different learning styles and rhythms. They also recognised the importance of international dimensions of education; flexibility of timetables; and collaborative work between peers. (Contains 1 table and 8 figures.)