This research investigates how foreign language learners learn vocabulary in an English as a Second Language (ESL) classroom. The participants are eleven foreign students from an advanced ESL Reading class in Edmonds Community College in Lynnwood, WA. A questionnaire was used as an instrument to inquire about the students' vocabulary learning methods. The results of the study proved that students are more engaged and motivated during group work activities and they learn more vocabulary from reading classes. The study concludes with pedagogical implications that ESL teachers might consider when teaching vocabulary in their ESL classrooms.