Math anxiety is a common correlate of math performance. However, the causal direction of this relation is unclear.Research with young students is limited but critical for determining patterns of development. Students (N = 147) completedmath measures (i.e., number comparison, arithmetic fluency, and math problem solving) and math anxiety assessmentstwice, first in grade 2 (Mage = 7 years:10 months) and then a year later in grade 3. Correlational analysis revealed thatmath anxiety is related only to arithmetic fluency, related to other types of math performance. Cross-lagged analyses wereconducted to evaluate causal relations between math anxiety and arithmetic fluency. These analyses showed that arithmeticfluency in grade 2 predicted change in math anxiety from grade 2 to grade 3, however, math anxiety in grade 2 did notpredict the change in arithmetic fluency from grade 2 to grade 3. These results suggest that math anxiety may be the resultof poor math performance.