Age of the Earth? How do we know?

Our latest ELI has just been published - 'Working out the age of the Earth - moving backwards as time moved forwards'.  Ask pupils to link up the ‘headlines’ about calculating the age of the Earth, to show how ideas about the age of the Earth have changed over time from 1650 when Bishop Ussher gave a calculation of 6000 years to 1956 when radioactive uranium/lead dating of meteorites gave an age of 4.55 plus or minus 1.5% billion years. In recent years radiometric dating has given the most reliable figures. They all cluster around 4.6 billion years, more easily remembered as near 4,567 million years.
This activity is another ELI which gives a good example of 'How science works'. Others include the work of Charles Darwin, James Hutton, Mary Anning and Alfred Wegener. All of these can be found using 'Search activities' on the home page of our website.

London's fossils; an ancient world hidden in the city

As part of our series on building stones, a reader has suggested that this video could be used when looking at sedimentary rocks.
You can see the ELI activities on building stones and lots of other great ideas for teaching science and geography on our website.

What is that building stone?

Find out by using ELI's building stone resources. We have written one activity as a general resource and one focusing on the igneous rocks. Today we have published an ELI that gives details about the sedimentary rocks used as building stones. Metamorphic rocks as building stones will be published soon.
What is used in your area? Can you write a building stones activity for the area around your school? Share it with others on this blog or on Facebook.

ELI is now on Facebook

 ELI is now on Facebook. Please have a look at this very new page and write a comment or just 'like' it! We will improve it as, hopefully, we get better at using it. If you have any suggestions, please let us know.
Also, we have just published our latest map of the countries and towns/cities that ELI has reached in the world. You can view this in 'ELI in the world' on our website.