http://www.tryscience.com/ Ideas and experiments from the New York Hall of Science. Organised into categories such as Earth Sciences, Space Sciences, Medicine and Health.
www.spartechsoftware.com/reeko/ Reeko's Mad Scientist Lab! A source of science and chemistry projects and experiments for parents, teachers, kids, and children of all ages
www.pbskids.org/zoom/activities/sci/ Lots of fun ideas covering all aspects science and engineering that would fit well into a one-hour Club session.
http://www.hunkinsexperiments.com/ Great ‘filler’ or ‘ice-breaker’ experiments which take about 5 minutes each. Most of these experiments use hardly any equipment and are great for catching pupils attention
www.scienceprojectideas.co.uk Lots of ideas for science projects covering Biology, Chemistry, the Environment and Meteorology and Physics. Also includes advice on running projects, as well as fun facts and trivia.