check with your local United Way. My FAVE volunteer event is the annual Day of Caring which is held in September. I'm not sure EVERY United Way hosts one, so you'd have to investigate. It's a huge one day regional volunteer event where teams select from a list of projects of just about every flavor you can imagine, all with the same purpose - to help those in need.
i've helped clean up a beach, help a senior center get ready for a white elephant sale (we taught them the macarena at lunch!), taking a group of physically/mentally compromised individuals on an outing to the zoo, helping a food bank sort and prepare food for home delivery, cleared a pathway in a neighborhood park on a really steep hillside for access to the newly UNcovered orchard that had been "lost" to overgrowth, feeding the homeless........i could go on, as i've been involved for close to 25 years..........