There is growing evidence to support the use of trial-based functional analyses, particularly in classroom settings. However, there currently are no evaluations of this procedure with typically developing children. Furthermore, it is possible that refinements may be needed to adapt trial-based analyses to mainstream classrooms. This study was designed to expand the trial-based functional analysis literature by implementing the procedure in 2 mainstream primary school classrooms and validating the analysis through comparison of multiple treatment options, including some that were not indicated by the functional analysis. We also extended the procedure by including a peer-attention condition and obtaining data from teachers regarding the feasibility of the procedures. For all participants, functional analysis results helped to identify effective treatments. Furthermore, relative effects among treatments were accurately predicted by the functional analysis outcomes. Teachers reported that they understood the logic of functional analysis and found both analysis and treatment procedures to be easy and effective.