For example, x^2 - 1 = 0 , 1 - x^2 = 0 and x^2 + 1 = 0 all look similar, but only two have solutions over the real numbers.
A copy of the slideshow I used will be posted next week after the conference. I will also post a link to the video of all of the talks when it is up. I would also post copies of the slides, but I have a lot of animation on each slide so it becomes a jumbled mess. A link to the video of the entire show will be posted about 10 days after the conference so you can see all of the talks. Below are the resources I mentioned in the talk. Thanks as always.
Using Rich Problems for Differentiated Instruction
The Homework Dilemma
The Organisation for Economic Co-operation and Development (OECD) Programme for International Student Assessment (PISA)