My son started participating in the library's summer reading program the summer he turned 2. We read and read and read and he loved attending the different programs and earning his reading medal. Each year we set a goal of reading more new books than the previous summer and discovered some great new books along the way.
As he got older, though, some things changed. First, when we moved to a different library system, the program was set up differently, so instead of setting a particular goal, every child has to read the same amount of books. Also, as my son got older he was reading more and more chapter books on his own instead of having books read to him. Of course, this is a natural progression, but I have found that sometimes he starts off really well and then kind of fizzles out after a few weeks. When I'm not involved in the books he's reading, it can be hard to keep him motivated.
This year I'm trying to get my kids excited about reading some new books with our own summer reading plan. For my almost 10 year old (oh my goodness! How is he already 10?!) I've selected five chapter books he's never read. For each book, he will have some kind of activity we'll do or field trip we'll take to go along with the story. For instance, one of the books he will get is The Marvelous Inventions of Alvin Fernald, and when he's done reading the book, he'll get some materials to try to make some of the inventions in the book and to try some of his own ideas. When he reads The Candymakers, we'll make some candy ourselves! Hopefully these activities will keep him excited and motivated and I think it's also a good time to get in some books I think he would enjoy and would like him to try out.
For my almost 5 year old (Ack! 5?!) I'll do something similar, though she will probably have more books since she's younger and her books are shorter. Pinterest is overflowing with crafts and activity ideas for picture books, so planning for her should be fairly easy!
Hopefully this will allow us to walk the fine line of encouraging the kids to read specific books without it being too much of a chore or assignment situation—not that that's always a bad thing, but I want to keep it simpler over the summer. I'll let you know how it goes at the end of the summer!