Mister Rogers' Neighborhood S01 E28 Things that fit into other things

"Won't you be my neighbor?"

Title number 0028. Opens with Mister Rogers arriving with nesting boxes. At the television house, someone sends a rather unusual box. After he locks his pillow in a safe, Edgar Cooke expresses his different feelings. Lady Elaine Fairchilde finds her special toy, which is a boomerang.