Do you follow my other site, the Latin Baby Book Club? Each year, we publish a summer reading list. And the 2011 edition is now live! This is a great resource for bilingual families who are helping their kids maintain their reading skills during the summer by participating in a library or online summer reading program.
These summer reading lists are super because they don't offer an overwhelming number of titles, but they do list a variety of books for newborns to young adults.
I already mentioned some great online programs, so I won't do that again. But don't forget that the LBBC and MommyMaestra also have some free printable reading logs in English and Spanish to help you and your kids keep track of their reading progress. (You can find them in my sidebar under "Free Downloads.")