You can switch between different family member's accounts without logging out fully from the app, using the 'Switch User' feature. This is helpful if your family shares a device.
You can find the 'Switch User' button by following these instructions:
Click on your profile photo in the top left corner to access the quick navigation
A navigation pane will slide out from the left
At the bottom of the navigation pane you'll see the button 'Switch user'
Click on this to see all available accounts setup for your family
From here your kids can login to their accounts using a pin, or if another parent would like to access theirs, they will only have to input their password to access their account.
This is also a secure way to lock your kids out of a parent account as they won't be able to access a parent profile unless they know the password you set up.