There is an Import option for User Attributes (Click Profile Name > Import Data).
Upload is via CSV, the file must contain the User Email Address, and any number of other columns for the Attributes.
Note that the Attributes must be created in EdSmart before they can be mapped to the fields in the CSV.
After upload, the columns can be mapped to Attributes.
NOTE: This feature is enabled on a per school account basis, you may need to Contact Support have it enabled for your school.