In this article, Lindsey Fowler describes how an animal rhyme--that she shared with her fifth-grade students with the intention of assisting them with the concept of metric conversions--made fostering the Standards for Mathematical Practice (SMP) more difficult. The addition of animals, which added an extraneous element that students mistakenly attended to--much like rules and tricks--instead of the mathematics, caused confusion because they started basing their mathematical reasoning on something that had no reason at all. In this article, the authors address four common animal troublemakers that hinder both content learning and practice development. The amount of time often devoted to instruction with animals could be spent on more meaningful mathematics tasks that support students in building understanding of the concepts and procedures, rather than simply memorizing a set of steps or skills. For each animal, the authors explain the trick or strategy and the problems with it, and they offer alternatives that are more mathematically sound and meaningful.