Brass instruments share many similarities, and teachers have fewer variables to manage in their pedagogical approach than in a woodwind sectional, for example. Breathing, buzzing, articulation, and the rest of the fundamental skills for playing each instrument may differ slightly in technique but have common principles that allow for relatively streamlined instruction in heterogeneous brass settings. The horn probably presents the greatest challenge when incorporated with other brass instruments but is still a more natural fit with other brass instruments rather than a pairing with a non-brass group in terms of the technical aspects of performance.
Heterogeneous groupings, whether all brass or all band instruments together, offer musical opportunities for listening and awareness that homogeneous groupings do not. Students can develop ensemble skills of blending, balancing, and tuning with unlike instruments as they learn how various instruments work. Conversely, teachers who have the option to work with single instruments have the opportunity to more easily individualize instruction, develop consistent conceptions of tone, and engage in in-depth material regarding each instrument. The effectiveness of all contexts depends on good teacher preparation and an environment in which students are engaged and understand the expectations for the class.