Adam Riccinto directs the YSO in an all-ages outdoor concert, the final one of the season. Bring a chair or blanket and enjoy a concert of popular and family-friendly favorites. With a guest performance by Gemini, the veteran local acoustic duo of twin brothers Sandor and Laszlo Slomovits. Rain date: May 28. Also, a Children’s Entrepreneur Market (2-5 p.m.), with vendors ages 5-16. 2 p.m., Riverside Park, Ypsi. Free; donations accepted. [email protected].