Teaching ideas

•   Decimals and integers on the number line (Teaching resource sheet 4)

This link displays some cards for you to print and some cards to enable you to make a number

Using Blu-Tack^®, put the integers from -5 to +5 along the wall at equal intervals. You could make the line on the floor or outside.

Either print off the cards given or write these numbers on pieces of paper.

Set 1:

-2            -2.5            -3            0               1             0.775         1.225

-0.25       2.7             2.55         -2.575       -0.7        0.75           -2.05        -1.25

Set 2:

-1.6          -0.067       1.4          0               -2            -3.04          0.36

-0.86        4.15           -2.5         -1.01        2.65        1.5             -3.8          3.74

Give each volunteer one number on a card or piece of paper and ask them to put their number on the number line.

You could use Blu Tack and students could attach their cards to the line. Once they have done this, ask them to take account of scale and move their cards apart or together so that they end up being about the right distances apart. For example there will be more distance between 0 and 0.7 than between 0.7 and 0.75.

•   Guess my number game (Teaching resource sheet 5)

This link displays the instructions for this game.

1. 1. Choose a leader.
   2. The leader chooses a decimal number less than 100 with between 3 and 5 digits.
   3. The rest of the class/group are allowed to ask questions to which the leader can answer yes or no.
   4. The student who finds the numbers is the winner.

Encourage students to ask questions like “Are there two digits after the decimal point?” or “Is the second number less than 5?” rather than “Is it 13.76?”. You may need to choose someone to record the answers on the board so that students don’t lose track of what they already know or encourage students to keep track of what they know themselves.

• I am taller than you (Note if you have any particularly tall or short students then you will need to consider whether doing this starter is appropriate. You could ask students to choose a decimal number between 1 and 2 with 1, 2 or 3 decimal places instead.)

Ask the students to write down their height in metres on a piece of paper, for example, 1.58 m

The whole group/class puts themselves in order from tallest to shortest.

Asks questions about how they did this.

Discuss which digit they looked at first.

Teacher notes

• Encourage students to write numbers using nested place value if they are having difficulty. So 0.7, 0.75 and 0.775 could be written as 700, 750 and 775 thousandths respectively.
• Encourage students to use or imagine a number line if they are having difficulty.
• Students should be reminded to read 0.69 as zero point six nine and not zero point sixty nine because otherwise they could think that 0.69 is greater than 0.7 because 0.7 is read as zero point seven.

Working with materials is the best way to help students understand why 0.69 is smaller than 0.7 etc.

Sometimes converting to fractions helps as well. 69/100 is smaller than 70/100. It also encourages students to understand the links between decimals and fractions and gives practice at changing between them.