This isn't only for kids, but it's a high tech GPS tracker you can use on anything and anyone. It weighs just over 3 ounces, is supremely compact, and has a battery life that lasts for days. You can set it to send notifications at regular intervals (2.5, 5, 10, 30, and 60 minutes), and it has motion sensors built into it to detect when you are on the move. It's easy to attach to a keychain or slip into a tiny pocket in your child's backpack, and though it's a bit pricey, it's worth it!
Updated: 3 years ago