Previous empirical studies have shown that solo entrepreneurs benefit from having balanced skills: Jacks-of-All-Trades (JATs) are better entrepreneurs than specialists are. Nowadays however, the majority of entrepreneurs start up and run ventures together in teams. In this paper we test whether the effect of more balanced skills is also positive in a team of entrepreneurs. We also explore whether (a lack of) individual balanced skills can be substituted by combining the skills of various specialists within one team. Our field experiment studies teams of children participating in an entrepreneurship education program. Based on pupils' precisely measured level of verbal and mathematical ability, we exogenously compose 179 teams separated into four different types: JAT teams, math-specialist teams, verbal-specialist teams and mixed specialist teams. Our results show that balanced skills are beneficial to team performance, and that it is hard to substitute individual balanced skills by combining different specialists within one team.