The Ministry of Education, Culture, Sports, Science and Technology in Japan (2011) started the 'Foreign Language Activities' in fifth grade based on the new Courses of Study in April of 2011. The ministry has considered beginning this course in third grade and the 'English Course' in 5th grade in order to improve students' reading, writing, listening, and speaking skills. The ministry also developed supplemental teaching instruments, such as the CALL system. The purpose of this study is to model and analyse the effectiveness of a speaking-pen on English learning among elementary school children in consideration of individual differences using a Liner Mixed-Effect Model. The authors constructed models representing students' overall abilities in four English skills, and analysed the effectiveness of the tools such as a speaking-pen and an audio CD on English learning in consideration of students' backgrounds including their English learning experiences and individual differences.