Registration is underway for winter classes for children and adults at the Leventhal-Sidman Jewish Community Center (333 Nahanton Street) in Newton.  Classes begin during the week of January 8 and are open to the entire community.  Classes for children include aquatics, ballet, dance, gymnastics, and soccer.  Classes for adults include painting, Pilates, basketball leagues, and child/infant CPR.  View entire listing of classes and register online at bostonjcc.org/register or call 617-558-6419.