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The ideas in this decimals lesson are taken from Math Mammoth Decimals 1 book ($4.00 download). Only a few examples of each problem type are shown.

Decimal numbers - hundredths
Free decimals lesson plan from HomeschoolMath.net

In the last lesson we divided the number line from 0 to 1 into ten parts and studied tenths.  We know that the distance from 0.0 to 0.1 is one tenth.  Now, repeat the same process as in the previous lesson and draw nine little lines between 0.0 and 0.1, dividing that into ten new parts.   If you repeated this process between 0.1 and 0.2, and then between 0.2 and 0.3, etc, how many parts would the number line from 0 to 1 be divided into? ______ How long are these new parts therefore? ____________  What fractions could you write underneath your little lines???

The number line below is a zoom in that goes from 0 past 0.3.  The interval from 0 to 0.1 has  been divided into ten segments again, and similarly the interval from 0.1 to 0.2 etc. [number line available in the ebook] The number 0.28 is read as twenty-eight hundredths and is the same as  28 100 . The number 0.56 is read as fifty-six hundredths and is the same as  56 100 . The number 2.34 is read as two and thirty-five hundredths and is the same as 2 34 100 . Write the fractions below the decimal numbers between 0.2 and 0.3 on the number lines above.

Example problem types

1.  Make a number line with the hundredths tick-marks... 

a)  from 0.6 till 0.7

d) from 90.9 till 91.2

2.  Fill in the missing hundredth parts on the number lines.  Read the numbers aloud.

3.  a) Make a long line, mark 1 in the one end of it, and 2 in the other end.  Divide the interval between 1 and 2 into ten parts, and write the corresponding decimals under the tick-marks.  Then divide the interval between 1 and 1.1 into ten parts.  Similarly divide the interval from 1.1 to 1.2 into ten parts, etc.  You probably won't have space to write the decimals that correspond to these hundredth parts.

b) Once you have the whole interval from 1 to 2 thus divided into hundredth parts, mark on this number line the following decimals:   1.55    1.11   1.28   1.39  1.88   1.02   1.67  1.99  1.74  1.43   1.90  1.06   1.20

4.  Write the corresponding mixed numbers below the decimal numbers on the number line.

[number line available in the ebook]

5.  Write in your notebook the following decimals in order from smallest to greatest.  If you find it difficult, draw first a number line from 6 to 7 as in exercise 2.

[available in the ebook]

Another way of illustrating hundredths is dividing something into hundred parts. This whole square represents one (1) whole. It is divided into hundred parts, so each part is ____________. This is twenty hundredths = 0.20 But it is also two tenths = 0.2, since each of the 10 columns is one tenth of the 1 whole. This represents 32 hundredths  = 0.32 This is 1 whole five hundredths = 1.05

 
6.  What numbers are the pictures illustrating?  Write as a fraction and as a decimal both.

a.

b.

c.

7.  Draw pictures like above to illustrate the following numbers.

Next lesson: Hundredths as a place value

The ideas in this decimals lesson are taken from Math Mammoth Decimals 1 book ($4.00 download). Only a few examples of each problem type are shown.