Background. Children and youth with severe cerebral palsy (CP) have limited independent mobility, which affects opportunities for overall development. Purpose. To examine the effectiveness of Power Fun, a therapeutic powered mobility summer camp. Methods. A quasi-experimental, repeated-measure design was used, with participants acting as their own control. Twenty-four participants with severe CP (aged 7–20 years) attended Power Fun for three weeks, five days/week. Assessments of powered mobility skills and functional mobility goals were conducted three weeks before the camp (T1), at baseline (T2), postintervention (T3), and at three-week follow-up (T4). Findings. An analysis of variance results indicated significant improvements in powered mobility skills (F(1,22) = 56.61, p < 0.001, η2p = 0.74) and functional mobility goals (F(1,58) = 80.17, p < 0.001, η2p = 0.74), with 70% of goals achieved postintervention. A descriptive analysis revealed three learning profiles. Implications. This study provides initial evidence supporting the effectiveness of Power Fun as an intervention promoting powered mobility for children with severe CP, across a range of abilities.