A guide to the best online science sites has been published by the UK Government's agency for schools technology.

The British Educational Communications and Technology Agency, which is leading the development of the National Grid for Learning, has identified how websites can be used in science lessons.

Science On-line presents secondary schools with classroom activities which have been integrated with specific websites - including the BBC's Planets site and pages from sites in science departments at a number of universities in the United States.

Educational tool

There are also links to school websites, such as at Buttershaw School in Bradford, West Yorkshire, alongside governmental websites, such as the United States Environmental Protection Agency's information on acid rain.

These websites illustrate the scientific activities with text, images, audio and video, and are intended to improve the quality of lessons - as well as teaching pupils how to use the internet as an educational tool.

The activities in Science On-line cover biology, physics and chemistry and include instructions for pupils and teachers' notes.

The publication will help schools to make greater use of the educational potential of the internet, an ambition of the government which is being promoted by the technology agency.