Educators are required to use evidence-based practices to support student development of academic skills. Results from single-case experimental designs are well suited for this purpose and may be more flexible for applied use than group-based designs. However, educators also require information about which interventions work for whom and under what conditions. Although previous reviews of single-case experimental designs exist, most focused on design characteristics related to internal validity. The purpose of this U.S. study was to determine the participant characteristics within multiple-baseline and multiple-probe across participant designs targeting academic skills. Representation of various demographic subgroups differ between studies targeting different academic skill areas (mathematics, reading, and writing). However, reporting was often inconsistent, with a substantial proportion of records omitting information about participants' race/ethnicity, economic status, and English learner status. This finding was divergent from best practice recommendations. Implications for future research are discussed within the context of the study's limitations.