The goal of this clinical trial is to test mindfulness practices in children with idiopathic chest pain, which is chest pain that does not have a known cause. The main question this study aims to answer is whether children who experience idiopathic chest pain are able to follow a mindfulness program. This study also aims to determine whether mindfulness affects the way children with idiopathic chest pain cope, and if it affects their stress levels, quality of life, frequency of chest pain episodes, and chest pain intensity. Participants will: * Complete a survey at the beginning of the study that asks questions about their sex, ethnicity, and history of chest pain and other chronic pains. * Complete a short survey every day for the entirety of the study that asks about the number, intensity, and duration of chest pain episodes experienced that day. * Complete 4 surveys, 2 weeks after they have been enrolled in the study: pain coping survey, perceived stress survey, quality of life survey, and mindfulness survey. * Be randomly placed into either the control group or the mindfulness-based intervention group, 2 weeks after they have been enrolled in the study. * Receive the standard of care for children with idiopathic chest pain, if they are placed into the control group. * Use the mobile app Headspace to complete daily mindfulness sessions for the remaining 30 days of the study (starting after the initial 2 week period), if they are placed in the mindfulness-based intervention group. * Complete 4 surveys at the end of the study: pain coping survey, perceived stress survey, quality of life survey, and mindfulness survey. * Complete a mindfulness program evaluation survey at the end of the study, only if they are in the mindfulness-based intervention group. Researchers will collect information from Headspace to see how well participants in the mindfulness-based intervention group are able to follow the mindfulness program. This will help guide future, larger studies that look at the effects of mindfulness-based interventions in children with idiopathic chest pain. Researchers will also compare survey results between the control group and the mindfulness-based intervention group to see if the mindfulness program affects the way children with idiopathic chest pain cope, as well as their stress levels, quality of life, frequency of chest pain episodes, and chest pain intensity.