Adult education in full-time colleges and universities is recognized by the state. Online registration, online search, credible.

Shandong University Shandong University of Science and Technology Shandong University of Science and Technology (Jinan Campus) Shandong Normal University Shandong University of Technology Jinan University Qingdao University Yantai University should all have adult education departments, and some are called continuing education colleges, which means adult education.

These are all good.