The New Victory, on 42nd Street, has been dedicated to children’s theater since 1995, and they know their business. They grant the tots that old-fashioned thing, an intermission; offer pre- and post-show arts activities; designate a play corner for the kid whose idea of fun is kicking the seat in front of him; and, most importantly, locate troupes, from all over the world, that make the underage set happy show after show. One such is Cirque Mechanics, a steampunk circus from Las Vegas that got its start by scratching a DaVincian itch for newfangled circus contraptions that enable trick to be piled upon trick. The show’s themes tend to revolve around machinery, too, though this season’s Yuletide Factory only nods to industrial magic and might. The restless workers of a grim, Depression-era factory produce juggling, rope climbing, contortion acts, trampolining, and all manner of holiday cheer. Ages five and up. —Apollinaire Scherr