Children and adolescents treated for a brain tumor often experience fatigue and cognitive symptoms, such as slowed information processing and inattention. These symptoms may cause difficulty carrying out daily activities at home and at school. There are few well-researched, non-pharmacological interventions aimed at improving symptoms of fatigue and by extension cognitive symptoms. Systematic bright light exposure has been shown to improve symptoms of fatigue in adult survivors of cancer and children treated for some forms of cancer. This is a pilot/feasibility study and the first known study in children treated for a brain tumor. Findings from this study will be used to help plan a larger study to examine the effectiveness of this intervention and mechanisms of action. PRIMARY OBJECTIVE: 1. To evaluate feasibility and adherence in a study of systematic bright light exposure used to improve fatigue and cognitive efficiency in survivors of pediatric brain tumor, including rates of enrollment, adherence, and acceptability. SECONDARY OBJECTIVES: 2. To estimate the effect size of change in fatigue associated with bright light exposure. 3. To estimate the effect size of change in cognitive efficiency associated with bright light exposure.