Michael wants to be able to keep track of his kids. Leo says that Apple has an iPod Touch with texting. But it needs WiFi to work. As soon as the kid leaves school, they aren't connected. That's why parents are giving kids cell phones now. Another option is an Apple Watch. But it's expensive because it has LTE built-in. But it would work. He can even set it up for secondary use. Android Wear watches also work like that. The Galaxy Watch 4 has that capability. Verizon also sells a watch for kids. Called the GIZMO. He could use Apple tags on their backpacks. But that's not a lot of "oomph."
From the ClubTwit Discord: There's also the Guardian Angel Kid Tracker. Also, Back 2 You Personal GPS tracking provider.
Here's a list of the 12 Best Smart Watches for Kids.