Heathside Schools Mathematics Department Lesson Plan Outline CONFIDENTIAL
| Teacher: Mr G Wilson
| Class: 8A3
| Date: 2-Dec-09
|
| Module/Topic: KS3: Perimeter, Area and Volume / Circumference of a Circle
| Room: T3
| Lesson: 13:55-14:45
|
Lesson Objectives (including AFL)
- Review homework -- help them to add and subtract areas.
- Learn and apply the formula for the Circumference of a circle.
| Success Criteria
- Everyone able to remember and apply the formula for the circumference of a circle.
- Everyone able to write π and know its approximate value.
|
Class Management Objectives
- Continue with EB's strategy to keep them largely quiet and on task.
|
| Lesson Context (including AFL)
| Prior Pupil Knowledge
- Area of various quadrilaterals
- Perimeter
|
Resources/Equipment
- Whiteboard pens
- IWB pen
- 35 copies of Starter worksheets
- 35 copies of main worksheet
- 15 copies of Extension
- 35 copies of homework sheet
- Strips of graph paper for estimating π.
- This lesson plan (two hard copies)
- Whiteboard rubber
- Spare calculators
- Mega-compasses
- List of star students on PowerPoint
- Two examples from Monday's homework on ActivStudio flipchart
| Provision for EAL/SEN/G&T
|
Health and Safety
- No abnormal risks -- today will be just worksheet and whiteboard.
- Students may need to use compasses (for circle construction).
| Named Students
|
Starter
- Review specific homework problem about adding and subtracting areas.
- Some of the shapes were a little more complicated than the quadrilaterals we have been looking at.
- Break them down into shapes you know the area of.
- Area of the whole shape is the sum of the areas of the parts.
- Where you are asked for the area of a shaded part, you will have to do a subtraction.
- Area of the shaded part is the area of the whole shape minus the area of the unshaded part.
- Sometimes they may not directly give you the length of a side: you may have to work it out.
- Issue worksheet.
- You can use a calculator if you wish.
- 5 minutes, starting now.
- Write title of today's lesson -- π (Pi) and circumference -- and the date on the whiteboard.
- Take the Register while they are doing it.
- Review answers.
- Show the list of star students for this and previous homework. Issue merit stickers at end.
|
Development activities (including AFL)
- Today we're going to meet a new symbol.
- So far in maths, you've encountered a number of symbols: +, - ...
- Can you tell me some more symbols you already know (e.g. = x and /)?
- Today we're going to learn about a symbol called π. Nothing to be frightened of -- it's just a number. And we use it when we are calculating various values of circles.
- And in order to introduce this number, we're going to do a short practical.
- (Draw a circle on the IWB.)
- Can anyone tell me what we call the distance around the outside of the circle? (perimeter, circumference)
- Can anyone tell me what we call the line from the centre of the circle to the outside? (radius)
- And can anyone tell me what we call the line that goes through the centre and touches the edge at both ends? (diameter)
- (Draw various circles of various sizes on the IWB.)
- Notice how the larger the circle is, the larger its diameter, and the larger its circumference.
- In fact, man has known for thousands of years that the circumference is a constant value times the diameter. And that value is Pi.
- Circumference = pi x diameter
- C = π x d
- Can you copy this down please?
- So we're now going to do an experiment to see if we can measure what pi is.
- I want you to work in pairs, where you can -- i.e. with the person sitting next to you.
- To do this, you will need a ruler and a calculator between you, and the strip of paper I am going to give you.
- What I want you to do is to fold the strip over a random length -- just to ensure we all measure different sized circles. I want you to measure the length of the strip using your ruler and write it down. This is going to be the circumference of your circle.
- Then I want one of you to form a circle out of the strip, while the other uses the ruler to measure the diameter. Write down the diameter.
- Then I want you to use your calculator to calculate pi = C/d.
- Let me know you have finished by putting up your hand.
- Create a table on the board of the results.
- Make the point that pi cannot be expressed as a decimal or a fraction with total accuracy.
- 3.14 and 3 1/7 are approximations. As a decimal expression, pi goes on forever. The Japanese have used a computer to calculate the first 16 million decimal places.
- The first 10 decimal places for pi are on the poster below the ceiling as you walk down the passage outside. Watch out for them next time you are there.
- If interested, 22/7 is the best approximation containing numbers below 100.
- And 355/113, discovered by the Chinese, is the best approximation below 103,993/33,102.
- Main worksheet: p.52 of Kroll and Mills: 'KS3 Measures, Shape and Space -- Year 9'
|
Plenary / AFL
- "If, next lesson, I show you a worksheet of circles of various radius or diameter, how confident will you be that you can calculate the circumference? Show me the R-Y-G from your diaries."
- "Those of you showing me yellow, can you tell me what the difficulty is?"
|
| Cross-curricular links (Literacy, Numeracy, Citizenship, Spirituality, ICT)
|
| Homework
|
