Can I make multiple find my friends accounts off of one apple id to see my children's locations?

You have to create separate iCloud accounts with separate Apple IDs on each device in order to do this. You can continue to share the same Apple ID for purchasing, however; it does not need to be the same as the ID used for iCloud.

Go here: https://appleid.apple.com and create a separate ID for each device. Then go to Settings>iCloud and set up a different iCloud account on each device using a different ID. Then launch the Find My Friends app on each device and log in using this iCloud ID.