Regional School Unit 21 (RSU 21) includes the towns of Arundel, Kennebunk, and Kennebunkport, Maine. We are three tight-knit small towns with approximately 18,000 residents. Our seaside and rural landscapes welcome visitors from around the world, and we have a great quality of life. We have more natural, cultural, and historical amenities than you typically find in towns our size. We love where we live, and invite you to get to know us.