The organization for which my daughter and I volunteer meets outside for crafts at the picnic tables of our local park. We often hang the finished crafts in the tree to dry while we take nature hikes to search for baby animals and bullfrogs. After hiking for approximately 20 minutes, we return to the tree, distribute crafts, and send the little ones back to their adults.
I keep students motivated during the summer by treating the summer months no differently than the fall, winter, or spring. As a homeschooler, I have the option of doing so. I school year-round because I don't believe in breaks in learning. My husband is a public school teacher and complains every year about his students' loss of skills during the summer. I suggested telling the parents to treat learning as a life skill rather than something their children do from September-June. We all should always be learning those things which will help us throughout our lives regardless of age or season. Instill a love of learning and knowledge at an early age and continue to nurture it, and you will never have to worry about motivating a student, again.