Some of my favorites growing up (and my mom's as well)
Younger:
Alexander and the Terrible Horrible, No Good, Very Bad Day by Judith Viorst
The Monster at the End of This Book by Michael Smollin
Charlie and the Chocolate Factory by Roald Dahl
Older:
The Stinky Cheese Man and Other Fairly Stupid Tales by Jon Scieszka
The Ordinary Princess by M.M. Kaye
the Wayside School books by Louis Sachar
the Secret Garden by Frances Hodgson Burnett
Where the Red Fern Grows by Wilson Rawls
From the Mixed-Up Files of Mrs. Basil E. Frankweiler by E. L. Konigsburg
I'll still sit down and read all of those books when I come across them again
