This is a 2x2 lattice you can print out and use in class or at home. I would print these out and put them in sheet protectors. The kids would write on the protectors with dry erase makers. They could erase and use it over and over. It was a huge timesaver, because the kids didn't have to make a new lattice for each problem. They could even put their markers and their rags in the protectors when they were finished with their lesson. It's an economical alternative to dry erase boards!