Here are some examples of state-specific extensions to the Ed-Fi Data Standard.
State
Extension Link
AZ
https://www.azed.gov/information-technology/azeds/developers
IN
https://www.in.gov/doe/it/link-initiative/data-exchange/#Data_Exchange_Ed_Fi_API_Suite_3_v6_0_for_Developers
NE
https://www.education.ne.gov/dataservices/adviser-resources/#1533221816265-b51e789f-abfc
SC
https://ed.sc.gov/data/information-systems/interoperability-resources/ed-fi-in-south-carolina/
TX
https://www.texasstudentdatasystem.org/tsds/teds/ods-upgrade-data-standards
WI
https://wisconsindpi.atlassian.net/wiki/spaces/widpiedfi/pages/2294032/Data+Domains+Endpoints+Integrations