Safe Room Heaters

Does anybody have any good suggestions for room heaters? My daughters' bedroom stays cold all winter long. The new ductwork and furnace we installed does nothing for their room. I worry about safety so I'd need good recommendations on the safety and effectiveness of a good room heater.  We'll need to do something in there by November.  Otherwise, they'll spend five months piled under a load of blankets to stay warm and I'll spend the winter getting up in the middle of the night, every night, making sure they are covered up.  I'd kinda like to sleep this winter.