SCO A7: Students will be expected to read and represent decimals to thousandths.

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SCO A7 Students will be expected to read and
represent decimals to thousandths.
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Introductory Activity 1

• Draw a number line with a starting point of 2 and
  an ending point of 4.
• Examine the following list of decimal numbers so
  that you can properly preheat your number line.
  
• 2.51 3.490 2.3 2.999
• 3.01 3.409 3.75
• Next, place each decimal number at its correct
  position on the line. Be prepared to explain your
  thinking.

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Introductory Activity 2

• Making the connection
• between decimals and fractions
• Suzanne went to the store and bought 6.25 L of
  juice for a birthday party. How is this amount
  read?
• How is this amount read as a fraction? What is
  another fraction we can use to represent this
  amount?
• How is the amount 4.75 kg read as a decimal and
  as a fraction? What other fraction represents
  this amount?

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Introductory Activity 3

• Decimal numbers can be used to represent very
  large numbers.
• For example, the number 5.1 million represents
  the number 5 100 000
• What large number does 3.4 million represent?
  What large number does 3.5 million represent?
  What large number does 3.54 represent?

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Introductory Activity 4

• Estimating and Reading Numbers
• 18.5 can be read as 18 and 5 tenths or more
  usually as 18 and ½
• How can the number 6.497 be read as a fraction?
  What everyday fraction is this amount close to?
  (about ____)
• 48.73 is about ????
• 12.254 is about ????

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Student Activities

• A7.1
• Work with a partner. Take turns tossing three
  dice. Make the largest number you can using the
  digits to represent tenths, hundredths, and
  thousandths. Show this same number using base-ten
  blocks. How much would need to be added to this
  amount to make one whole?

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Student Activities

• A7.2
• Examine the different displays of combinations of
  base-ten blocks. Record the five decimals shown
  if the large cube represents 1 whole.

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Student Activities

• A7.3
• Gasoline is priced at 75.9 cents per litre. What
  part of a dollar is this?
• Home heating oil is priced at 65.7 cents per
  litre. What part of a dollar is this?

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Student Activities

• A7.4
• Write the decimal numbers for two hundred
  fifty-six thousandths and two hundred and
  fifty-six thousandths.
• Explain why watching and listening for and is
  important when interpreting numbers.

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Student Activities

• A7.5
• Newspapers sometimes use decimal numbers to
  record numbers. For example, a newspaper might
  use 2.5 million instead of 2 500 000. Do you
  think this is a good idea or not?
• How might a newspaper show 4 300 000 using a
  decimal number?
• What about 7 540 000?

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Student Activities

• A7.6
• A student was given the instructions Please cut
  3.25 metres of ribbon for me.
• How many centimetres of ribbon is this? How do
  you know?

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Student Activities

• A7.7
• I was thirsty and drank 0.485 litres of water.
  How much more would I have had to drink to equal
  0.5 L?

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Student Activities

• A7.8
• Examine newspapers and magazines to see when 0.5
  and ½ are used.

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Student Activities

• A7.9
• Write four different decimal numbers that have
  tenths, hundredths, and thousandths.
• Make base-ten pictures that would represent these
  numbers.
• For each amount, tell how much more would be
  needed to have a whole cube. Write this showing
  using a subtraction sentence.