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									                   L.O.1
To recall multiplication facts up to 10 x 10
Don’t draw the table just write the missing answers in order in your book.



   X       5       7       3       9       4       2       8       6

   5      25                                              40

   6                      18

   7                                      28

   4                                                              24

   9                                              18

                                                    2 ½ minutes
Which multiplication facts are hard to
      remember?

      Why do you think that is?

    Which are easy to remember?
                   L.O.2
   To understand area measured in square
                        centimetres
   To begin to understand the formula
“length x breadth” for the area of a rectangle
  What do we mean by the word “area”?

 Show where the area of your table top is.



REMEMBER…
 The area of a 2-D shape is the amount
 of surface within its perimeter.
Q. How can we work out the area of this rectangle?
We can do it by counting the squares.
 The rectangle has 24 squares
  Its area can be written as
24 square centimetres or 24 cm².
       Draw 2 rectangles in your book.


Write the dimensions and areas next to each.

    Be prepared to explain your working.




Q. Is there a quick way to find the area of a rectangle?
You should find that multiplying the
number of squares in each row by the
number in each column gives the area.

These numbers are equivalent to the
  length and the width / breadth.

So the area of a rectangle can be written
   as length x breadth or length x width.
Check this theory by drawing more rectangles:
         Prisms draw 6
         Spheres      5
         Tetrahedra 4

but consider….
 Q. If you double the length of a rectangle what
 happens to its area?
 Q. What would happen to the area if you
 doubled the length and the width?
             This is a patio.
 Each paving slab measures 60cm by 60 cm.

Q. If we had used 30cm by 30 cm. paving slabs
      would we have used twice as many?
We would have used 4 times as many because we
need 4 small slabs to cover each large one.
Q. How can we find the area of this shape?
          4 cm




6 cm
            A
                                    B
          4 cm

We can do it like this - by turning it into TWO shapes, inserting
the missing dimensions then adding the two areas A and B.
           4 cm




4 cm
             A

2 cm
                        B


       or like this……
Use either method to work out the area of this shape then
draw a similar shape but with dimensions half the size.

       Calculate the area of your new shape.
.
                  2 cm
                         4 cm

                                  1 cm


                 6 cm


    You should have something like this.



    Its area should be 10   cm²
.    Using this shape repeat what you’ve just done.




    You may need to make 3 areas this time.
By the end of the lesson the children should
         be able to:
   Express the formula for the area of a
   rectangle first in words, then in
   letters.
   Choose a suitable unit to estimate the
   area.
                 L.O.1
To be able to use doubling to multiply
       two-digit numbers by 4.
   To halve any two-digit number.
We are going to double these numbers:

63           18            47

       52             66            39

56           27             98

       77             95            41
We are going to halve these numbers:

64            78            20

       52             48               66

42            74            32

       50             96               22
If we halve these numbers how can
      we express the answers?
Will they be fractions or decimals?

23             87             65

93             31             47

59             75             19
               24
Q. What is a quick way to multiply
       this number by 4?
Doubling twice is the quick mental method to
               multiply by four.

 We’ll multiply each of these aloud by 4.

       23            55            34

  18         87             76          39
                  L.O.2
To be able to understand area measured
        in square centimetres.
To understand and use the formula in
    words “length x breadth” for
      the area of a rectangle.
                        cm²
We used cm² to find the areas of shapes in yesterday’s lesson.
                            Here we have a square metre.

                                         1metre

  How many cm² are
  there in I square
  metre?
                           1metre         1m²
  How can we work it
  out?
              1m² = 10 000cm²

      because    length = 100cm.

        and     breadth = 100cm.

and     100cm x 100cm = 10 000cm²
               1mm²
   Try to imagine a millimetre square

Q. How many mm² are there in 1cm²?

Q. How can we work it out?
           1cm² = 100mm²

 because    length = 10mm

   and     breadth = 10mm

and 10cm x 10 cm = 100mm²
Which of the three units ( m² ,cm² , or mm²)
  would be best for measuring these?

1.   The classroom floor.
2.   An exercise book.
3.   A postage stamp.
4.   The playground.
5.   A chocolate bar wrapper.
6.   A mouse mat.
7.   Your thumbnail.
.

                                          2.8 cm


                        6.1 cm


The area of a rectangle is length x breadth or l x b for short.

Here the area would be 6.1 x 2.8 but it is useful first to get an

                      ESTIMATE
    Q. What is the approximate area of the rectangle?
.

                                       2.8 cm


                      6.1 cm


    Rounding UP and DOWN leads to an approximate area of

                      6 x 3 = 18cm²
Let’s try with these:


  1.                            1.7cm


              5.9 cm
Rounding UP and DOWN leads to    6cm x 2 cm = 12cm²


  2.                                           3.2cm


                        11.8cm

Rounding UP and DOWN leads to 12cm x 3 cm = 36cm²
.



    With a partner complete
      Activity Sheet 7.1
. In which rectangles do you
 think the area has been
 underestimated?


 Using calculators we’ll check
 your estimates but will round
 part-answers to the nearest
 whole number.


 Q. What areas of shapes in
 the classroom would you
 measure in mm², cm², or m²?
 Record about a dozen
 altogether.
In your book draw rectangles using cm and mm and
write their length and breadth. Be accurate!
Your partner must first estimate the area by rounding up
or down then work out the area to the nearest whole
number using a calculator.
Record both the estimate and the final answer.

Tetrahedra draw 2
Spheres draw 3
Prisms draw     4

Extension: measure area to two decimal points.
By the end of the lesson children should
        be able to:
   Express the formula for the area of a
        rectangle first in words then in
        letters.
   Choose a suitable unit to estimate the
        area.

								
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