Quentin D’Souza on TeachingHacks.com says
I have used this in maths with an extra bit. Find a regular shaped feature on a map – say a football pitch – and ask children to measure it using the line and path function. Then calculate the area. Add complexity by taking an irregular shape – such as a park – and get them to work out the approximate perimeter and the approximate area (this can depend on age – children can split the shape into other regular shapes they are able to calculate, triangulate the shapes – or, even do this in secondary school at an advanced level using calculus!!)
Check their answers using line and path function. (Click on the ruler on the top menu bar)
Have also used this with secondary pupils to look at the ratio of green space to built up areas in a given area as part of an environmental project.