My son drug the Preparing Hearts guide around the house and EVERYWHERE last year. He had it right by him for ALL experiments and things got on the cover multiple times. Yet, the book stayed bound, the cover wiped clean over and over, and the corners of the book are still intact at year-end! The sides of the pages are a bit pencil marked here and there, but overall I was thrilled with the way the guide held up. I must tell you that almost every other guide we've ever owned (from other curriculums with our older son) has not held up in this way, so I'd encourage you to try leaving the manual as is. You may be pleasantly surprised. I know I was! Blessings,
Carrie