Is there better way to celebrate St. Patrick’s Day than attending a waltz? Of course not! (For teetotalers, that is. Alcohol’s a no-no in Glen Echo.) The weather will be perfect for dancing to CONTRATOPIA: Patrice Pakiz (piano, oboe), Erik Sessions (fiddle), Theodore Hodapp (melodeon, concertina), John Goodin (mandolin, guitar) and Pat O’Loughlin (English concertina, banjo, cajón and Irish harp–okay, the last one’s a joke). As always, there’s a beginner waltz lesson at 2:45, included with admission of $13 per person ($5 with valid student ID). Music from 3:30-6:00. No partner necessary and EVERYONE is welcome.