The scoutmaster has the final say as for what can constitute as a service project, but before approaching him with their idea, scouts should consider whether or not their project is providing any actual services to the person/group of people for whom they are performing the service.
As a guide, the Scoutmaster will look at the benefit the scout receives for performing the service. If a scout receives payment, cash or otherwise for his own scout account or the troop general fund, for performing a task, then those hours will likely not be approved service hours. If however donations are accepted during the course of providing a vital service to an organization, then it is possible those hours could be approved service hours. This will be decided on a case by case basis at the sole discretion of the scoutmaster.