How to close the achievement gap in the classroom so that no student is left behind becomes one of the most important issues nowadays. This study aims to construct a collaborative and competitive game-based learning environment to improve English proficiencies and reduce the achievement gap for disadvantaged students. The Wireless Crossword Fan-Tan Game (WiCFG) system was implemented to provide teachers with an innovative approach to guide students' learning through a positive involvement with the uses of tablet PCs. The experiment was conducted in an elementary school in Taiwan to investigate whether this approach would facilitate students' learning effectiveness and interactions. Thirty sixth-grade students were randomly assigned into a control group and an experimental group. Both qualitative and quantitative data were collected from surveys, interviews, observations and video-recordings. The results indicate that integration of the WiCFG system in the collaborative and competitive game-based learning environment leads students to a better interaction between different levels of students. This innovative approach might have the potential to close the achievement gap for disadvantaged students. Moreover, some principles of the classroom strategy are suggested as guidelines.