The purpose of this study was to examine the effects of a short-term English program designed for work-study college students on the learning outcomes and experiences. We analyzed changes in TOEIC scores, learner beliefs, and learning experiences of 24 students who participated in the six-week program. Changes in learning experiences were analyzed through sentiment analysis of learning diaries using Google Natural Language API. Our findings showed that the outcomes varied according to the attendance rate, with the high attendance group showing a statistically significant increase in TOEIC scores. As for the changes in learner beliefs, the high achievement group showed increased positive beliefs about learning outcomes and confidence while the low achievement group perceived learning English as difficult, and their confidence remained unchanged. Sentiment analysis of learning diaries to evaluate the changes in learning experiences showed a V-shaped curve for the sentiment scores of the high achievement group whereas the low achievement group’s scores decreased as the program progressed. Based on the word cloud and qualitative analysis of the diaries, the key learning obstacles were irregular attendance, lack of study time, and difficulties in understanding the lessons.