I use this at the beginning of the year to help my students identify appropriate books for their reading level. We discuss what a downhill book is since when we go downhill it is too easy, an uphill book maybe too difficult, and what a just right
This is a reading challenge I made for Spring Break last year. My students loved it. It really pushed some of them to read a lot. I've provided it in editable form as you can modify it for Winter Break, or number of minutes, ect.