Seventy-seven ESL students from grades 4 to 6 participated in a pretest-intervention-posttest design study to investigate the affect of two Computer Aided Language Learning (CALL) programs in comparison to regular ESL instruction on language and literacy skill development. One CALL listens to students reading and gives feedback on misread words, and the other displays text while it reads to students. For all conditions, students made significant pretest to posttest gains across measures, with the exception of phonological awareness for which a trend was found. No significant differences in language and literacy skill gains were found across the conditions. The interaction between stage of English language and literacy development and language and literacy skill gains was also examined. Regardless of condition, early-ESLs made significantly greater gains in word level reading, and there was a trend towards intermediate-ESLs having greater gains in listening comprehension and reading comprehension. Implementation of CALL is discussed.