Somerville’s annual ArtBeat festival operates under the idealistic, if not quite novel, philosophy that kids and adults can have fun together. Indeed, the event, rechristened “ArtBeast” this time around, didn’t stick to the usual plan of putting magicians, puppet shows, and other kids’ stuff on early in the day while reserving the more mature fare for the dark. At Seven Hills Park, behind the Davis Square T station on Friday July 20, the ArtBeast line-up was rigged so that if the youngsters wanted to check out the animated “Beastly Fim Shorts” at the end of the bill, they had to first take in the Bennet Dance Company’s poetic “Ladder Dances,” the Berklee indie orchestra the Young Republic, and the “sophisticated noise pop” of Bon Savants. This led to an uncomfortable moment when an ArtBeat rep in a bunny costume took the stage following the Young Republic to request donations. The bunny joked, “Does anyone know what makes the Money Bunny happy?” And some idiot twice yelled out, “Anal sex.” This didn’t fly with a father up front with his child. “Come on!” he appealed . . .

Later that night, Harvard Square was transformed into “Hogwarts Square” in honor of the release of the seventh, and final, Harry Potter novel, Harry Potter and the Deathly Hallows. There was much to behold: a crowd of steadfast Potterheads who remained glued in front of the Harvard Coop awaiting the book’s official unveiling at midnight; a flock of folks who took to the streets in wizard and witch gear, with wands, ties, and sweater vests; and the homeless person asking for donations to save Hogwarts. But the biggest spectacle was in Harvard Yard, in front of Memorial Church, where Harry and the Potters — Paul and Joe DeGeorge’s J.K. Rowling–inspired rock band — performed songs about Ginny Weasley, Hagrid, and Voldemort. What the band lacked in ability, they more than made up for in energy and ingenuity. They had people cheering for everything from the defeat of the Dark Lord to J.K. Rowling to the citric-acid cycle. Later, some furious pogoing commenced on the grass during a song about how “the one thing we have is love.” After that, everyone dispersed, I assume looking for a quiet place to read.