Every summer, the news is filled with stories about summer learning loss. The warnings sound dire: two months of math learning lost for most students every summer, and two to three months of reading learning lost for low-income students, according to the National Summer Learning Association. By the ninth grade, "summer learning loss during elementary school accounts for two-thirds of the achievement gap in reading between low-income children and their middle-income peers," the association says. There can be no doubt about it: as American children lounge poolside, watch too much television, and play too many video games, most are forgetting what they learned in school last year, and low-income students are falling even further behind. It sounds plausible. But how reliable are these claims? How many of these findings can be replicated? Is summer learning loss really a thing? The author used to be a big believer in summer learning loss. But his belief has been shaken. In this article, he describes several things that happened to challenge his faith.