Smartboard Galleries

The other day I was trying to explain why you cannot combine (through addition and subtraction) terms in an algebraic expression with different variables or different exponents. My students were just not getting it, and I was faced with the frustration that only math can foster in students' attitudes. I then remembered that there were some algebra tiles in the smartboard gallery. I popped those on the screen so that the equation was not just numbers and letters, but tiles of different colors and sizes. The students could then clearly see that x squared can't go with x, they are different. Thank the lord for smartboard!