## Listing all results (27)

### Ordnance Survey Maps

This film, from Twig World, looks at the history of ordnance survey maps. Ordnance Survey has been creating maps for hundreds of years. How have their mapping methods changed since the first Ordnance Survey maps were made?

The key points made in the film are:

•The British Ordnance Survey team are the...

### Time Zones

This resource, from Twig World, looks at time zones around the planet and how these changes affect people.

The key points made in the film are:

•There are 24 time zones, which are regions on Earth that are bound by longitudinal lines. •Local time depends on what time zone you are in. •The system of...

### How long is a Metre?

This three minute video, from Twig World, explains that the metre is the base unit for measurement for most of the world, but how was it agreed how long a metre should be? The need for standardised units of measurement is discussed and the value of the metre being one ten millionth of the distance from the North...

### Jai Singh

This video, from Twig World, explains how the city of Jaipur in India was designed by the mathematician and King Jai Singh II. In order to ‘unravel the mysteries of the Heavens’, he built a series of observatories and the largest sundial in order to make the most accurate sundial in the world.

The video is...

### Rounding: Snails Vs Rockets

This video, from Twig World, explains how we are able to measure extremes of speed, from incredibly fast to extremely slow. The degree of accuracy required when taking these measures needs to be decided. This is achieved by rounding. Examples of unhelpful rounding are given and the need for the notion of...

### Speed of the Earth

This video, from Twig World, explains that the planet earth is constantly moving through space and models the Earth’s orbit as a circle in order to approximate the distance travelled in one year and hence estimate the distance the Earth travels every second. The video is accompanied by a lesson plan and a...

### Volume: Counting Stars

This video, from Twig World, begins by asking how do astronomers estimate the number of stars in the night sky. To explain how it is done, a method of calculating the number of grains of sand on a beach is shown. The same principles are used to estimate the number of stars in the sky.

The video is...