Integers Misconceptions

Why is it that so few of my pupils have a real understanding of performing calculations with negative numbers.

I have recently been working on finding the equation of a line in slope-intercept form with my S3 class. They investigated how to calculate gradient and have a great understanding of how to calculate gradient. The problems arose when actually calculating the gradient. So many errors with calculations such as -4 – (-5).

Listening to conversations at various tables I hear statements like “two negatives make a positive” and “I hate negative numbers”. The main misconceptions seem to be that since 6 – (-3) = 9 then -3 + (-4) = 7 since two negatives make a positive.

Quadratics Misconceptions

There are many common misconceptions that my pupils have. Many of them relate to simplifying algebraic expressions.

This week there have been two particular misconceptions gathering momentum around my Higher maths class. We have been completing work on stationary points and optimization – which relies on being able to solve quadratic equations.