Did a foreign language in the elementary schools (FLES) program in a Kansas school district affect students' academic achievement in English?

What happens to English academic achievement when valued class time is devoted to a foreign language in the elementary schools (FLES) program? Is there a reduction in achievement as suggested by a time-on-task hypothesis, or is there some form of compensation, as suggested by additive bilingualism? The school district in this study started a FLES program with Grade 2 students in five schools in 1995-96, and the students continued FLES through Grades 3, 4, and 5. Students in the other eight district schools received no FLES. The FLES and no-FLES students were compared based on the Grade 6 Iowa Test of Basic Skills (ITBS), using Grade 2 ITBS Survey Battery to control for initial variation in test scores. No significant statistical difference was found.