Nate the Great and the Stolen Base by Marjorie Weinman Sharmat illustrated by Marc Simont*

My first grader read this book to himself.
Rosamond's baseball team uses a purple plastic octopus for second base.  One day it is stolen!
Nate the Great and Sludge need to find second base before the next game.
*Highly recommend.
-Borrowed from the library.
Guided Reading Level: K (end of 1st grade/beginning of 2nd)