ABSTRACT
Too often, in an attempt to help, adults tell students what to do and how to do it, or offer mnemonic devices, without paying attention to the conceptual mathematics behind all those instructions. The ubiquitous acronym FOIL can be a useful mnemonic device when multiplying two binomial expressions, but the device is useless when multiplying expressions that are not binomials or when there are more than two binomial expressions to multiply. The distributive property, the more general mathematical law that FOIL exploits, is relatively straightforward to use without mnemonic tricks. Many students are able to model multiplication of binomials by binomials using Algeblocks or by sketching the model, which is sometimes referred to as “drawing window panes”.
