I think the least aired episode is neither Spongebob SquarePants House Party or Spongebob ScaredyPants/I Was A Teenage Gary,I haven't seen House Party for a while and I haven't seen the Scaredypants/I was a teenage gary since last halloween.But I think they air each episode in order from episode one to the last season four episode they air,but holiday episodes,they always only sometimes air it on the holiday *cough*Once A Year*Cough :dry: