stumbling blocks

Turning stumbling blocks into building blocks.

building blocks

These resources give ideas for addressing common misconceptions.  They are free to download and adapt.  

Each section address a key concept in mathematics that is an important  building block for many other topics.

The minus sign

The minus sign is a potential minefield of misconceptions because it has so many different meanings. The meaning can even change part way through a problem!

The minus as opposite (inverse)

Click here to download Rethinking the minus sign powerpoint with video.

The minus sign has multiple meanings, and this can cause confusion and lead to misconceptions.

In this presentation I introduce the minus as opposite (inverse).

One sign, one meaning, no confusion!

Base Blocks

Base blocks are a powerful tool to explore the structure of the base system from base 2 to base x.  This deepens students understanding of base 10 and can be used to address misconceptions with the four operations.  It is also an excellent introduction to manipulating algebraic expressions using algebra tiles.

The ideas in this section are inspired by Exploding Dots adapted from by James  Tanton.  

This version stacks counters rather than exploding dots.  This exposes the exponential growth of different bases.  


The same concept can be applied using multi link cubes exposing the geometrical structure of the base system.

Mathsbot has an easy to use set of interactive Dienes blocks in different bases.

More coming soon …