SCO A2: Students will be expected to interpret and model decimal tenths, hundredths, and thousandths.
What do we mean by a whole number? What does a whole number represent? How do we draw one?
What do we mean by a decimal number? What does a decimal number represent? What can we draw to show a decimal number? What are some uses of decimals in our everyday lives?
Look at the picture on the board. What does it represent? Now let’s subdivide the square into 10 equal parts. What is the amount of each of these smaller parts using a fraction? Using a decimal? How is this amount read? (Give two ways.)
How would you show hundredths on a grid? How would you show 0.03? Shade another grid to show 0.30?
Now let’s use the base ten materials to show decimals. Let’s have a large cube represent 1 whole? What would a flat represent? A rod? A small cube?
Student Activities A2.1 Model 0.025 using decimal squares. How does this model differ from the model for 25 hundredths? Model both of these amounts using base-10 blocks. What block did you use to represent the ones place? Why?
Student Activities A2.2 Identify (find and tell) the decimal represented by the shaded portion of the diagram shown to you if the hundred grid represents 1 whole. How much more is required to make a whole?
Student Activities A2.3 Place the decimal number 0.75 on a metre stick where you think it belongs. Place the decimal number 0.265 on the same metre stick. Now place the other cards shown to you on the metre stick.
Student Activities A2.4 The number 0.452 can be represented or expressed as: 452/1000 45/100 + 2/1000 4/10 + 52/1000 Express 0.135 in at least three different ways.
Student Activities A2.5 Identify some situations when 0.25 represents a small amount. Now identify some situations when 0.25 represents a very large amount.
Student Activities A2.6 A new bakery slices its loaves of bread into 10 equal pieces, then makes bread sticks by cutting each of these slices into 10 equal parts, and then makes croutons by cutting each of these bread sticks into 10 equal pieces. Model this using the base-10 blocks. Which part of the loaf is 1 slice? 3 slices? 1 stick? 5 sticks? 1 crouton? 9 croutons? 2 sticks and 3 croutons? Now use the blocks to show 0.2 loaf; 0.14 loaf; 1.5 loaves; 0.5 slice; 0.25 slice; 0.7 stick; 0.3 stick.