The fall foliage is fantastic.
Nashville has events year-round, but fall is definitely the best time for families. It's a lot less crowded, and the weather is mild, so you and your kids won't be zapped by the humidity. If you time your trip right, you'll be in town to catch the leaves changing color. The Ganier Ridge Loop Trail will take you through the Nashville hills, where trees turn amazing shades of red, gold, and orange. If you're up for a short hike, the city has four nature centers that have easy trails for kids.