Hot and Cold Cubes Positive and Negative Counters

thingiverse

Learning addition and subtraction of positive and negative numbers can be a challenge to many students. Traditionally, students model using a number line and arrows indicating magnitude and direction, however, this representation has its short comings. An alternative approach is to model with positive and negative counters. A hook activity for this is using a story called Chef's Cubes, by Interactive Mathematics (http://mathimp.org/), which relates traditional counters to hot and cold cubes used to control the temperature of a magical soup. I have had great success in using this hook activity but I do not have any manipulative for students to get their hands on - they are limited to drawing + or - signs on their paper. This model is to overcome that and get the cubes in their hands so they can make a richer connection between the story and how to effectively model addition and subtraction of positive and negative numbers through the use of hot and cold cubes. Project: Hot and Cold Cubes Objectives: Students are expected to make their own hot and cold cubes to use as manipulatives in modeling addition and subtraction of positive and negative integers. This can be expanded upon to model multiplication and division of positive and negative numbers as well. Audiences: Grade 6 and 7 mathematics students. Preparation Students should already know the four basic operations with positive integers. Steps Begin with reading the Chef's Cubes story (available online: Link) Then have students print their own cubes to use - if this is a linked learning or STEM/Maker class, have them design and print their own customized versions of the cubes Once they have a set of cubes, they can then progress through the operations with positive and negative integers. Begin with demonstrating what a hot cold and a cold cube would be equal to when added: 1 + (-1) = 0. This concept of a zero-pair is essential for modeling with cubes. Then move onto having them add in zero pairs of cubes (one hot and one cold) so they can resolve simple situations For example: 5 - 8 = - 3. This would start with 5 hot cubes, then since we are removing a larger number than we started with, we have to add 3 zero pairs. documentation and lesson plans can be found on modeling with positive and negative counters. Results Through the use of tangible cubes, students show an increased connection and understanding to the concept of addition and subtraction of positive and negative integers.