The Blade has an article about Saturday's Maple Syrup Day in Williams County. I have visited several farms out that way and I've always enjoyed a glimpse into the farming life. Many farmers maintain a woodlot in the center of their fields; if it's maple-dominant, they call it the "Sugar Bush" and make syrup.
Pancakes and sausage will be served at the Williams County Fairgrounds from 7:30 to noon on Saturday, 3/24. Wagon rides across a covered bridge will take visitors to the maple trees and the sugar shack where syrup is made. Admission and wagon rides are free; breakfast must be purchased. Other things to buy include fudge and cotton candy made with maple sugar.
It's a long way to go for just one event, so I can recommend other stops: a side trip to Lake La Su An Wildlife Area or Harrison Lake State Park, maybe lunch at an old-school country diner called Stokes on U.S. 20, and don't forget to visit the enormous red marble teddy bear, a poignant headstone in the Pioneer Cemetery (on 20), visible from the easternmost road.
Goll Woods near Archbold is known for its early-spring woodland wildflowers on the way back. It's a good place for woodpecker sightings. There's an old French cemetery in the center. The woods suffered significant tornado damage last year -- it makes for an eerie landscape, seeing huge broken trees all along the road.