Within public school systems, a variety of school types coexist nowadays, each with its own distinctive features. Proponents of school choice claim that differentiation fosters innovation and raise standards – but it this true for all school types? Within the public school system, free choice should not outweigh equality of opportunities, and parental choice should be informed by comparable effectiveness measures. In this paper, we estimate the relative effectiveness of several secondary school types operating in the English school market. We use the school assignment mechanism and rich administrative data from Birmingham to identify and estimate causal effects. We find that selective grammar schools provide substantial academic returns – despite being attended by the most talented students. Stark changes in peer composition for attendees hint at ability peer effects as the most likely mechanism generating this result. On the contrary, autonomous academy schools do not generate positive returns – irrespective of whether they are ‘conversions’ or ‘take-overs’. Finally, we find non-positive and insignificant effects also for faith school attendance. This is the first attempt at estimating the effects of different school types within the same education market (Birmingham) and using a single identification strategy (RDMD), based on the assignment mechanism.