Area In Addition To Volume

Every maths region should ain a giant lawn tennis ball! Walk into the classroom alongside a large fluorescent ball nether your arm in addition to you've at in i lawsuit got the attending of the class.

Students stand upwards inwards a circle in addition to are told they're entirely allowed to speak if they're belongings the ball. Ask "how could nosotros function out the surface surface area of this ball?" in addition to throw it to a random student. Students throw the ball around the circle equally they portion their thoughts in addition to propose ideas. At some signal a instructor prompt may last necessary, along the lines of, "why did I select a lawn tennis ball? Why non a football game or netball or golf game ball?". In my sense this prompt may atomic number 82 some students to 'eureka' moments equally they starting fourth dimension thinking almost the markings on the surface of the lawn tennis ball. Eventually mortal volition topographic point that the surface is made upwards of iv circles wrapped around each other, in addition to they tin so deduce that the formula for the surface surface area is 4πr². If they demand convincing, demonstrate them this slide.

This is a rattling engaging activity. As pupils can't speak unless they're belongings the ball, you'll run across them wildly waving their arms about, silently begging their friends to exceed them the ball so they tin portion their ideas!

Try it - I'd dear to listen how it goes.

Area in addition to majority is a broad ranging topic, from areas of triangles inwards Year seven to volumes of hemispheres in addition to frustums inwards Year 11. Here's a handful of my favourite resources:

• I manus out these rhymes for the surface area in addition to circumference of a circle in Year 7, tell them to alternative their favourite or come upwards up alongside their own. Love this silly song too.
• Also for Year 7, these matching cards from the Nuffield Foundation involve calculating the surface area in addition to perimeter of chemical compound shapes.
• As always, enough of dandy activities on teachitmaths.com. 
• At GCSE I purpose this problem solving challenge with questions from Median Don Steward. Pupils function on A3 newspaper inwards pairs. They demand their brains switched on for this one. There's loads of vivid activities on Don Steward's blog that could last used inwards a similar way.
• The Chalk Face has some lovely activities, including: cornflakes problem; Penny Farthing; fuel tank; golden balls and baby surface area. 
• There's a nice activity on finding the majority of dissimilar shaped glasses from Shell Centre. 
• Illustrativemathematics.org has fantastic geometry activities. I dear the rich chore Eight Circles which relates to finding the surface area of a circle.
• The Chalk Face also brings us this dandy harder surface surface area questions from Don Steward.
• Maths Sandpit has a fantastic resources for investigating the surface surface area of a cone.
• Challenging volume in addition to surface area revision questions for Year 11. Some of these are quite tricky in addition to demonstrate that this topic isn't but almost substituting into formulae.

For related degree intelligence - why produce nosotros nation hemisphere but semicircle? Why non semisphere or hemicircle? I believe it's because the intelligence circle is from the Latin intelligence circus (meaning ring), thus nosotros purpose the Latin prefix semi, whereas sphere is from the Greek intelligence sphaira (ball), thus nosotros purpose the Greek prefix hemi. This article almost semi/hemi/demi gives to a greater extent than examples. If y'all similar this so y'all powerfulness also similar these lovely maths vocabulary activities.

Finally, here's i for the teachers. It's non equally obvious equally it seems!

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