You don't need to know if a dune is parabolic or linear to enjoy climbing its crest or taking a memorable ride around it in a jeep, but it's interesting to explore the P.J. Hoffmaster State Park and its dune-centric Gillette Visitors Center.
The center provides a good introduction to what you'll find elsewhere in the park but concentrates on the 3 miles of Lake Michigan shoreline and towering sand dunes. One fun exhibit compares sand samples from Oregon, North Carolina, Massachusetts, Colorado and P.J. Hoffmaster and provides an explanation for the differences in color and texture. Other displays discuss how nature has shaped the ubiquitous dunes and touch on regional history.
From there, head straight onto the dunes via a raised walkway and stairs to Mt. Baldy, one of the area's highest dunes. The view from the top affords a scenic peek at Lake Michigan over a hilly expanse. The park also offers camping with modern sites and restrooms (from $27), plus guided nature programs and authorized metal detection areas.