Participation in the Spectra Discovery study lasts one week. Your child will wear three lightweight devices: a pair of fake glasses and a shirt clip, both equipped with light sensors to measure surrounding and screen-related light exposure, and a small waist-worn activity counter to track movement. They'll also use a study-provided Android tablet preloaded with their favorite apps, including an app called Chronicle, which automatically tracks screen time. This helps us evaluate how well the wearable devices measure screen use compared to digital tracking. As a parent, you'll first complete a 25-30-minute online survey about your family and your child's screen habits. Then, you'll meet with a study team member (at home or in our Chapel Hill office) for a one-hour orientation to learn how to use the devices. During the week, you'll help your child wear and charge the devices, encourage tablet use, complete a nightly 20-25-minute time-use diary via text, and log when devices are worn. You'll also briefly monitor an app called Screentime and ensure all devices are charged nightly. At the end of the study, you'll complete a 20-25-minute follow-up survey and return the materials in a brief closing visit. Children will receive a thank-you gift, and families are compensated for their time.