Words –> Expressions

I deal with this all of the time. I think it helps to do numerical expressions before going algebraic. Students quickly see why 4 less than 10 is 6 and should be written 10-4. But even after understanding, they still tend to make a mistake here…variables are a bit too abstract. I also emphasize that when they hear “less than”, a lightbulb should go off over their heads and they should remember that there is something special about it.