This paper investigates the factors influencing changes in students’ TOEIC test scores in the first year of study at university. Reading circles focusing on interaction between students were introduced into English classes and this research is based on the prognosis of a connection between aspects of discussion activities and TOEIC performance. The participants for the research were 321 first year university students. The results suggest low individual orientation has a connection with increase in TOEIC score. Furthermore, decision tree results indicated a relationship between the efficacy of students’ English abilities and a significant increase in TOEIC score.