In her work concerning algebraic thinking, Kieran notes that students learning algebra tend to fall into two groups—“algebraic” thinkers who use undoing as a way to solve equations, and “arithmetic” thinkers who use trial-and-error substitution to solve equations. “Algebraic” thinkers rely on inverse operations; for example, this group would solve 5 + a = 12 by saying 12 – 5 = 7, ignoring the variable itself. When these students move on to more complex equations, such as 3a + 3 + 4a = 24, they tend to overgeneralize and get stuck (“24 divided by 4, minus 3, minus, um, no, divided by 3”). They are unable to balance the equation because they have not assigned enough significance to the role of the equal sign within the equation- solving process (Kieran 1988, p. 94). When arithmetic learners speak of their solutions, however, because they are using trial-and-error substitution, Kieran finds that they discuss the balance required between the two sides of the equation. She further states that of these two, “arithmetic” thinkers are using a method that “may provide a more intuitive basis for the more structural solving methods” (1992, p. 401). I was curious to see if an eighth-grade student whose thinking could be characterized as “arithmetic” would indeed find this type of thinking a help or a hindrance to her further development of algebraic concepts.