All 3 books are Wonder Books Easy Readers from 1961/62
They are in prette good shape for their age, some edgewear and scuff marks:

Mr. Pine's Mixed-Up Signs Story and Pictures by Leonard Kessler
Billy Brown Makes Something Grand Story by Tamara Kitt, Pictures by Rosalind Welcher
Fly-Away Air Show Story by Leone Adelson, Pictures by Andree Goblin (Name written in pencil inside)

Will combine shipping