Once you have completed your tagging, you should write all the metadata to the files. (Select them and press Ctrl+W)
You can then use the File>Export command to save the files to a thumbdrive or whatever you are going to use to send the files to your children. They will then import the files from the storage device and will have an opportunity to import the keyword tags with the files. If the tags don't exist on their computers, the keywords will be created for them.
However, face tagging information will not be carried over. You can get around this issue by tagging the files with not only the face tags, but also with a keyword tag with the same name as the person. Once imported to the children's computer, they will be stored in the Imported keyword tag category. They can then select all of the files with the person's keyword tag and apply a People tag (newly created if necessary) to those files. (Or they can wait for face recognition to create the tags.) Until face recognition has been performed on the files, the thumbnail icon will be a generic one in the People room because the file will not be associated with a face in the photo. Face recognition is required for that to occur.