Non-formal learning settings enable self-selected groups of children to participate in out-of-school activities related to their interests, with participation primarily governed by intrinsic motivation. In contrast, formal learning incorporates external rewards through assessment activities which engender extrinsic motivation. Here we describe an exploratory study carried out in computing clubs for primary-aged children, held outside the formal curriculum in schools and libraries. The objectives of the study, involving 12 clubs and 115 children aged 6 to 11, were to investigate the feasibility of introducing assessment opportunities to computing clubs and to consider the impact of rewards in this context. Children worked on programming projects, and were given quizzes to complete at the end of club sessions, with children at some of the clubs being given both quizzes and 'rewards' charts, with badges for completing the projects. We found that quizzes with badges were favourably received by both children and educators. Results indicated that including badges as a form of tracking and rewarding progress significantly increased enjoyment of the assessment activity. This study is part of a larger study looking at learning outcomes in computing clubs, and has implications for others in non-formal computing settings.