I did it this way:
One of my favorite days of the year involves us celebrating our reading year by creating signs to show off the number of books we read for the whole school year. It's one of my favorites because I invariably have students who, although they've been keeping track all year, when it comes time to write that number to show off, realize just how much they've really read, and that it's much more than they ever could have imagined. As my students were making their signs, I heard comments like, "I can't believe I read that many books!" "I read way more than the 40 you challenged us to read!" "I read 30 more books this year than last year!" "I'm going to read even more next year!"
The first step to helping students develop into stronger readers is to get them reading. A lot. My 7th & 8th graders do that. Here's the record of our success and celebration.