From the Schema.org Blog:
Schema.org version 3.5 has been released. This release moves a number of terms from the experimental “Pending” area into the Schema.org core. It also simplifies and clarifies the Schema.org extension model, reducing our emphasis on using named subdomains for topical groups of schemas.
New terms introduced in Pending area include improvements for describing projects, grants and funding agencies; for describing open-ended date ranges (e.g. datasets); and a substantial vocabulary for Educational and Occupational Credentials.