flunk out

from the GNU version of the Collaborative International Dictionary of English.

• intransitive verb to be dismissed (from a school or course of study) due to failure to perform up to the minimum standard.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• verb idiomatic To fail to finish school, or a given subject or course, due to academic shortcomings; i.e., to have too many flunking or failing grades (marks).
• verb idiomatic (of an educator or institution) To impose failing grades on (a student), often requiring a retaking of the course or academic year.