I thought some here might enjoy doing this with their kids...
If you bring in a reading log with 8 books, they can pick out a free book from a set list.
I know for my kids, completing reading log programs helps with integrating reading into our summer.
Ds1 does his school summer reading challenge, the library one and this one.
Ds2 just does the library one, as he is too young for the others.
If you know of any other ones, please share them!