Area Together With Volume

Every maths division should ain a giant lawn tennis ball! Walk into the classroom amongst a large fluorescent ball nether your arm as well as you've straight off got the attending of the class.

Students stand upward inwards a circle as well as are told they're solely allowed to speak if they're asset the ball. Ask "how could nosotros operate out the surface surface area of this ball?" as well as throw it to a random student. Students throw the ball around the circle equally they part their thoughts as well as advise ideas. At some quest a instructor prompt may last necessary, along the lines of, "why did I convey 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 showtime thinking virtually the markings on the surface of the lawn tennis ball. Eventually person volition topographic point that the surface is made upward of iv circles wrapped around each other, as well as they tin as well as so deduce that the formula for the surface surface area is 4πr². If they demand convincing, present them this slide.

This is a really engaging activity. As pupils can't verbalize unless they're asset the ball, you'll run across them wildly waving their arms about, silently begging their friends to move past times them the ball so they tin part their ideas!

Try it - I'd honey to withdraw heed how it goes.

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

• I mitt out these rhymes for the surface area as well as circumference of a circle in Year 7, tell them to alternative their favourite or come upward up amongst their own. Love this silly song too.
• Also for Year 7, these matching cards from the Nuffield Foundation involve calculating the surface area as well as perimeter of chemical compound shapes.
• As always, enough of dandy activities on teachitmaths.com. 
• At GCSE I role this problem solving challenge with questions from Median Don Steward. Pupils operate on A3 newspaper inwards pairs. They demand their brains switched on for this one. There's loads of bright 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 honey the rich line of piece of occupation 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 as well as surface area revision questions for Year 11. Some of these are quite tricky as well as demonstrate that this topic isn't only virtually substituting into formulae.

For related shape give-and-take - why produce nosotros tell hemisphere but semicircle? Why non semisphere or hemicircle? I believe it's because the news circle is from the Latin news circus (meaning ring), therefore nosotros role the Latin prefix semi, whereas sphere is from the Greek news sphaira (ball), therefore nosotros role the Greek prefix hemi. This article virtually semi/hemi/demi gives to a greater extent than examples. If y'all similar this as well as so y'all powerfulness also similar these lovely maths vocabulary activities.

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

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