When the pandemic hit, Stanford Economist Thomas Dee knew it was important to track enrollment as a means of understanding what children are experiencing. He discovered that 1.2 million students didn't enroll in public school. Dee's data indicates not only where these children went but also a significant number of children unaccounted for. 

A closer look at this data provides some insight into aspects of academic recovery that might also be missing.

"So much of our academic recovery discourse is focused on the kids still in public schools, and particularly those older kids who are in the kinds of testing windows that draw our attention," he says. "But the enrollment data are telling us really that some of the most substantial reductions in enrollment are among younger students, who to this day haven't yet aged into testing windows and won't until we hit the fiscal cliff, when the federal resources available to school districts run out."

The implications for such significant enrollment changes range from challenges in instruction, how to distribute funding properly, to possible layoffs and school closures.