LEMFO Q50 Smart Watch
This watch has built-in GPS so the location accuracy is much better than just use regular triangular location from cell towers. However, depending on if the kids are indoor or outdoor, the location can be either precise or off by roughly 0.5-1 mile. Keep this in mind.
Very light-weight and design for kids. The watch band is not too long for kids' wrist and made of soft/gentle plastic. They're comfortable to wear.
The watch has speaker and microphone so it's able to record and play back recordings.
Several kids' safety features: SOS dial, low power alarm, remote monitoring (hear what's happening near watch).