Choosing a career is an important biographical event for adolescents. Toward the end of compulsory education, they must decide which career path they want to pursue. The serious game like2be was developed to support adolescents in this individual career choice process. In a quasi-experimental intervention study with 809 adolescents, like2be was evaluated for its effectiveness in career choice classes at the lower secondary level. In addition, a teaching concept for the application of the serious game which included additional teaching materials was analyzed. The data show that like2be is an effective medium for broadening personal career choice horizons, especially when it is pedagogically well-founded and integrated into career choice classes. Although the effectiveness of like2be in stimulating intensive reflection on one's own vocational aptitude or a gender-sensitive attitude towards occupations is limited, the present study shows that like2be has major potential for supporting the process of career choice among adolescents.