Active Science  -  Primary and secondary notes, games and downloadable activities covering a range of science-related topics.
Association for Science Education  -  Includes details of membership, publications and conferences.
Brainpop  -  Uses Shockwave Flash movies to teach about health, science and technology. Also includes quizzes and information.
NASA Kids  -  Space-related facts and activities from NASA.
Primary School Science  -  Subscription service offering lesson plans, worksheets, clipart and other resources to support the teaching of Science in the Primary School. Some free samples available.
ScienceNet  -  Question and answer site for anyone interested in science.
Scienceweb  -  Primary science resources based upon the QCA schemes of work. Includes lesson plans, worksheets, questions and answers and contact details. Now a subscription service.
Science Worlds  -  A searchable database of science-related locations which are suitable for educational visits. Also includes links to science-based games.
Today in Science History  -  Births, deaths and scientific events on any day throughout time.
Yucky Science  -  Games, activities and other resources teaching children about the yuckier side of science.