Pete Seeger has been making children's records for over 50 years, but he has never made one like this, a full-scale collaboration with a group dubbed the Rivertown Kids who were, when he started working with them, fourth graders at the Forrestal School in Beacon, NY, where he lives. (At the time of the release of this album, they would be on summer vacation after finishing sixth grade.) The album's third credit, to "friends," includes a batch of other folk singers, some of whom sit in to take lead vocals on songs they wrote. Indeed, while Seeger is heard throughout the disc in one capacity or another, he can be considered something of a master of ceremonies, speaking or singing lead here, playing a banjo part there. While it is reasonable to classify the album as children's music, "educational" music might be a better tag, since the songs, written not only by folk singers, but also in some cases featuring lyrics contributed by the children, touch on familiar topics for Seeger, including political issues such as environmentalism and civil rights, as well as enough references to the Hudson River to make it a concept album about the waterway Seeger has devoted decades to trying to clean up. The children are not professional singers, of course, but their unison vocals remain in key and comprehensible for the most part, and they take turns singing lead on, for example, their own verses to "We Shall Not Be Moved," otherwise stepping back to allow Bob Killian to sing his composition "There'll Come a Day" or David Bernz to sing his "Solartopia," with Dar Williams taking a verse. Other singers who get lead vocals include Rick Nestler (on his song "The River That Flows Both Ways"), Travis Jeffrey (on "It's a Long Haul," which he and Seeger adapted from an old folk song), Dan Einbender (on his song "It Really Isn't Garbage"), and Sarah Underhill (on Bill Staines' "River"). Seeger, meanwhile, who demonstrated a remarkable vigor for his age at his 90th birthday concert at Madison Square Garden in 2009, here continues his late-in-life renaissance, following the same interests he's had throughout his life, and carefully transferring them to people young enough to be his great-grandchildren.