There are ways to determine - at least roughly - how many children have seen "Cars 2," or watched "SpongeBob SquarePants" this morning, or who are playing "Mario Kart" online. All you have to do is look at box-office figures, or Nielsen ratings, or make a phone call to Nintendo's PR department.

It's much, much, much more difficult, meanwhile, to estimate how many books area K-5 students have read to this, the halfway point of the 2011 summer break.

Charlotte-Mecklenburg Schools, as usual, sent home an "elementary suggested summer reading list" in June for rising kindergarteners through fifth-graders, featuring anywhere from 19 to 32 titles ranging from Eric Carle's "The Very Hungry Caterpillar" to Madeleine L'Engle's "A Wrinkle in Time."

CMS pays a lot of attention to performance-related data, particularly in the spring, when teachers and students become absorbed in preparation for and the taking of End-of-Grade Tests.

Then along comes summer, when students and their parents must fend for themselves. Unfortunately, a lot of families - especially low-income families - don't or aren't able to create a healthy environment for reading. If that environment doesn't exist, a kid could go 21/2 months without cracking open a book (particularly a kid who lives in a low-income area and depends on his or her school library for reading material).

EOG test scores for 2010-11 aren't yet available, but they probably won't change much from the previous year, when about 30 percent of third-, fourth- and fifth-graders in CMS scored as reading below their current grade level. We'll never get that number to zero. But can we get it to 25 percent? To 20?

It's possible that more structure - and funding - for a summer reading program would do it. Put several of the titles from the reading lists in kids' hands, and create book clubs that meet periodically throughout the summer so children can discuss what they're reading.

Or develop an incentive program that can be talked up during the last weeks of school and offers an exciting enough reward that kids will check in on each other's progress throughout the summer break.

The fight against summer reading loss has already been taken up in earnest by local nonprofit groups, including Partners in Out-of-School Time and Freedom School Partners; both have strong summer reading programs.

But Freedom School Partners, for instance, was hoping to reach 1,000 kids this summer. There are tens of thousands of elementary schoolers in CMS.

Interim CMS superintendent Hugh Hattabaugh will have a lot on his mind until a permanent replacement for Peter Gorman is hired. That successor will unquestionably have a pretty full plate.

But whoever takes over needs to do more to ensure kids keep reading skills every bit as sharp during summertime as their movie-going skills, and TV-watching skills, and video-gaming skills.