For us working in schools we thought it be pretty cool to make a solar powered lighthouse. Below you will see our model and link to the hand book explaining how it works. I hope this sparks some creativity.
Link to handbook- https://docs.google.com/document/d/1zMdaj8ulZzTI7dQl13WvgsPNqhlTvRT_65y5Yv0fcbA/edit?usp=sharing
Here you see a model for a solar powered lighthouse that (in theory) could be placed at a lake or ocean to help guide boats back to land. Also note that lighthouses are in the sun the entire day and are not blocked by any trees or buildings. This would make it a perfect location for solar panels!
Think about your house and community... can you think of any places that have extended exposure to sunlight and could benefit from solar power?