Project-based learning (PBL) with computers has become a topic of interest, and there has been a call for research to determine whether they facilitate learning and motivate students. This case study examines how English as a second language (ESL) adult learners' proficiency with prepositions was affected by project-based learning with enhanced input, explicit instruction, and production practice using the software program Hot Potatoes. The 14 participants were part of an intermediate ESL class offered by a Midwestern community college in the U.S. The students were divided into three different levels: low, intermediate, and high. The students then were divided into three main mixed-level groups, and each group was given a handout with a different set of grammatical rules. Each group was asked to create a 16-item multiple-choice quiz based on the rules in the handout. Following this, each group entered another group's 16 multiple-choice quiz into the software program, Hot Potatoes. In the final stage, each group took a Hot Potatoes quiz made by another group whose work they had not yet been exposed to. In addition, the students studied a list of 16 prepositions outside of class; the list was not part of the project. The students took a pre-, post-, and delayed posttest and were interviewed about their opinions about the project and the list.

The results of the one-way repeated measures analysis of variance (ANOVA) showed that there was a significant gain in pre-post test scores for the project. Although preferences and scores did not correlate, qualitative findings suggest that the intermediate and high-level students preferred the project, whereas the low-level students preferred the list. Ten students used strategies that were used during the project, such as forming rules for prepositions or finding example sentences on the Internet, to help them study the list. Thus, the qualitative data suggested that students transferred the strategies to a new context. Eleven students stated they would like to do a similar project in the future.