To order a given list of integers on the number line, students should start from the right side of the number line and move towards the left of it when they place each of the given integers on this line. The number line contains 0 and the positive and negative integers. Numbers to the right of 0 are the positive integers, while numbers to the left of 0 are the negative integers.
An example of ordering numbers on a number line is to use the list of numbers containing -9, +8, -5, +20, 0, and -15. Starting from the right side of the number line, a student should move towards the left until the integer -9 is reached, and circle it. A student uses this same method until all the numbers on the list are placed on the number line. Ordering the numbers from this list from least to greatest on the line gives -15, -9, -5, 0, +8, and +20. The least integer is -15, and the greatest integer is +20.