Semester 1 Topic 3 Level I

Task Name : Multiplying and Dividing Negative Number Stories Task Level : I (Year 8)
Semester : 1 Topic : Directed Numbers VC Strand : Number and Place Value
Web Address : http://maths.crusoecollege.vic.edu.au/npvI
Equipment Needed : Poster Paper
Victorian Curriculum outcome : Carry out the four operations with rational numbers and integers, using efficient mental and written strategies and appropriate digital technologies
Task description : Students create eight stories that describe multiplication and division of positive and negative numbers. Two should describe the multiplication of positive numbers; two should describe the division of positive numbers; two should describe the multiplication of negative numbers; and two should describe the division of negative numbers. Each story should contain: the written story; a picture accompanying the story; a number line describing the story; and an algorithm describing the story.
Assessment options : Photograph of poster; digital image.
Teacher notes : Money is a good way to describe these processes. If I gain three paypackets of $50 each, the effect on my wealth is +50 x +3 = +150. If I lose two of these paypackets, I lose positive money: +50 x -2 = -150. If I gain three bills for $25 each, I gain negative money: -25 x +3 = -75. However, if I lose two of these bills, I lose negative money which impacts positively on my wealth: -25 x -2 = +50.