Commander Toad and the voyage home
Jane Yolen
Commander Toad leads the lean green space machine "Star Warts" to find new worlds but runs into trouble when he sets course for home.

by Mark Shulman (2004)
Fillmore the boy and Geary the robot, who live on Planet Zada, take their robotic dog Sbot to other planets so that he can learn to act like a real dog.
Jane Yolen
Commander Toad leads the lean green space machine "Star Warts" to find new worlds but runs into trouble when he sets course for home.
David Ward
Chris Graham, a student at a science academy on one of Jupiter's moons, becomes involved in a secret project to build a sentient humanoid, not knowing that the device is intended for destruction.
Andre Norton
When Earthmen got into space, they found advanced races who deemed Earth far too barbaric to join them. They were assigned the only task deemed suitable, mercenaries on other backwards planets. Kana Karr, Arch Swordsman, Third Class, has his first assignment on Fronn. However, there they find weapons that belong only to the Galactics, and mechanized Terrans, all illegal. They must fight the entire planet to find a way to return and warn Central Command.
Victor Appleton
An alien probe found wrecked on one of Jupiter's moons and containing insane "intelligence" is stole from a laboratory before its secret of stardrive is obtained.