The Mushroom Planet Series
This is a group of children’s books by Eleanor Cameron. Two boys build a space ship and fly to a planetoid named Basidium. There, they meet the Mushroom People and have adventures.
Books in the The Mushroom Planet series:
David and Chuck take Theo Bass, Tyco Bass’s cousin, to the Mushroom Planet, unaware that a young astronomy professor has stowed away on board.
Mr. Bass’s Planetoid (1958)
David and Chuck are off in their spaceship to rescue the world from the Brumblitron.
Two short stories in which David and Chuck take a dream journey then help Mr. Bass recover a brumblium meteorite. This was written as an elementary school reader.
Chuck and David are drawn into a battle against evil as Mr. Bass searches for the stolen necklace of Ta that can protect the Mycetians from destruction.