The aims of this study were to assess the factorial and construct validity of the Subjective Exercise Experiences Scale (SEES; McAuley & Coumeya, 1994) among children. Following a pilot study designed to check British children’s comprehension of the instrument, two groups of children completed a modified SEES prior to and after taking part in a game of rounders (n = 110) or a maximal exercise test (n = 121). Confirmatory factor analysis revealed a good fit of the hypothesized model to the data after the removal of two problematic items that were identified by examining residuals and modification indices. Multisample analyses supported the generalizability of the factor structure across gender pre- and postexercise and across exercise mode. Analyses of pre- to postexercise changes in subscale scores gave some evidence for construct validity. The findings suggest that the modified SEES may be useful in examining questions concerning exercise and affect among children.