This article provides informative insights into the failure of many Stakeholders to attain the desired Ugandan private secondary schools, to realise their desired revenue and how that failure has caused critical investment concerns due to negative impacts on expected returns on investment. Therefore, the study drew upon that to explore whether preventive control practices within the COSO control activities contribute to this failure. The study used an interpretivism approach and was guided by conceptual COSO control activities component model. Data was collected using skype interview and thematic narrative technique was used for analysis. 16 internal stakeholders as Boards of Governors, head teachers, deputy head teachers, accountants and auditors were purposively selected from four private secondary schools located in central Uganda. Results indicate that control activities within the guidelines, segregated duties and IT environment in private schools’ financial management are ensured in the mobilization of desired revenue. However, efficiency, reliance and compliance differ in a positive or negative influence. Therefore, this study is relevant for internal stakeholders in private school businesses to ensure designing effective COSO control activities policies that influence preventive financial controls for achieving desired revenue to avoid bankruptcy.