If you've heard of Rumspringa, it was probably a scene of debauchery in a movie. But I hear that Rumspringa is not nearly as extreme in reality.
Rumspringa is an Amish custom to allow adolescents to explore beyond Amish culture to see if they prefer "modern life." The Amish live without many of the material goods and services that we live with, the power grid the most notable.
After Rumspringa, the youths can choose to commit their lives to the Amish lifestyle or leave for the modern world.
Around 90% of Amish choose to remain. Rumspringa allows the youths to see beyond what they've grown up with. It allows them to confront mimetism. Only by exploring the unknown can you know if the known is right for you.