Year 2 Lesson Plan 3: Fraction and Decimal Conversion

  1. (5 min) Mental Math
    1. Take 7.2 and multiply by 100 [720]
    2. What is 25% of 20? [5]
    3. What is 10% of 40? [4]
    4. Take the number of days in a week, divide by 2, and multiply by 10 [35]
    5. Take the number of inches in 1 foot and multiply by 2 [24]

  2. (5 min) Review of homework #2 (approx 3 problems)

  3. Pass out the fraction/decimal and percent handout and use it in the following discussion:
  4. TO CONVERT A FRACTION TO A DECIMAL:
    Divide the numerator (number on top) by the denominator (number on bottom). Use your calculator. First put the numerator into your calculator, push the divide key, and then put in the denominator.

  5. TO CONVERT A DECIMAL TO A FRACTION:
    Put the number in the numerator (without the decimal point) and in the denominator put in a 10, 100, 1000, etc. with enough zeroes so that the number in the denominator has one more digit than the number in the numerator. After, that, you should reduce the fraction to its simplest form. If you have a scientific calculator that does decimal to fraction conversion, do not use it for this project.

  6. TO COMPARE FRACTIONS AND DECIMALS:
    Convert the fractions to decimals, as we showed you above, and then compare to see which is larger or which is smaller.

  7. SPECIAL NOTE:
    When serious mathematicians deal with fractions, they write the divide sign as a horizontal bar. Now it is time to STOP using the divide sign with two dots, and also STOP using the slash (/) to write fractions. This is important because next week we will be practicing cancelling.

  8. Hand out In-class exercise. If students finish the In-class Exercise early, check their work and then you can hand out homework.