Fifty-four students were followed over 10 years and tested with native language measures in first through fifth grades and measures of foreign language aptitude and foreign language proficiency in high school. All students had completed two years of Spanish, French, or German. Students were divided into three groups based on their scores on the Foreign Language Classroom Anxiety Scale (FLCAS). Findings showed that the low anxious group scored significantly higher than the high anxious group on all native language measures beginning in the second grade. The low anxious group scored significantly higher than the high anxious group on all measures of foreign language proficiency and foreign language aptitude, and also achieved higher foreign language course grades. Few differences were found between the low anxious and average anxious groups on the native language and foreign language testing measures. Findings also showed that the FLCAS was negatively correlated with native language measures of reading, spelling and vocabulary as early as the beginning of first grade. The results suggest that the FLCAS is likely to be measuring students' perceptions of their language learning skills, and that language skills are likely to be a confounding variable in the findings of researchers who suggest that anxiety plays a primary role in foreign language proficiency and achievement. This article is relevant to all languages. (Contains 4 endnotes and 4 appendices.)