Engaged Driver Training System (EDTS) is a tablet-based training method which was developed to elevate hazard perception skills of teen drivers. The objective was to investigate the effectiveness of the EDTS training program on drivers' hazard perception skills in driving situations. Drivers' situation awareness was measured by mapping eye movements and verbal protocols of teen drivers to Endsley's model of situation awareness. Thirty-two drivers were randomly assigned to two groups: the experimental and placebo group. Drivers' situation awareness was first measured at one week and six months after training via an 8-mile on road drive. The situation awareness of drivers in two groups were compared with each other's in four categories of driving scenarios: crosswalks, turns, 4-way intersections, and rotary. Results show that in most of the categories the EDTS training had both short-term and long-term positive effects on drivers' hazard perception skills.