Parents should look for benchmarks of educational quality (curriculum, feedback, scaffolding, learning theory, and development team) to distinguish good apps from the abundance of poor-quality apps available in mobile app stores. If parents instead base their choices on user ratings or the app's ranking in the top charts of the education category, they risk selecting apps that do not offer quality educational experiences for their children. Thus, the present study investigates how ratings, rankings, and educational benchmarks impact parents' choices of educational apps. One-hundred and forty-nine parents of children in kindergarten to grade 6 viewed and evaluated 18 researcher-created educational math app pages. Results from a repeated-measures MANOVA and non-parametric tests revealed that parents were more likely to download, pay more for, and rate apps higher when they had positive user ratings, with a large effect, and parents generally preferred apps with bottom rankings, with a medium effect. Yet, the effect of educational benchmarks on parents' decisions was unclear. This study demonstrates an important problem in parents' app selection: when user ratings are available in app stores, parents rely heavily on this poor source of evidence of educational quality to choose apps for their kids. To address this, researchers should develop trainings and guidelines to help parents evaluate educational quality, and app stores should improve their rating and ranking systems to facilitate the selection of high-quality educational apps.