elementary school , English learner , local educational agency , secondary school , and State educational agency has the meanings given such terms in section 8101 of the Elementary and Secondary Education Act of 1965 ( 20 U.S.C. 7801 ). (10) Exclusionary discipline The term exclusionary discipline describes school policies and practices, whether formal or informal action of school officials or by law enforcement, used to discipline students by removing them from their regular learning environment. (11) Gender identity The term gender identity means the gender-related identity, appearance, mannerisms, or other gender-related characteristics of an individual regardless of the designated sex at birth of the individual. (12) Informal removal The term informal removal means an administrative removal of a student from the learning environment for part or all of the school day, or an indefinite period of time, without documenting the removal as a suspension or expulsion or engaging in formalized disciplinary processes. (13) Indian Tribe The term Indian Tribe has the meaning given the term in section 4(e) of the Indian Self-Determination and Education Assistance Act ( 25 U.S.C. 5304(e) ). (14) In-school suspension The term in-school suspension means an instance in which a student is temporarily removed from a regular classroom for at least half a day but remains under the direct supervision of a school official. (15) Mechanical restraint The term mechanical restraint has the meaning given the term in section 595(d)(1) of the Public Health Service Act ( 42 U.S.C. 290jj(d)(1) ), except that the meaning shall be applied by substituting student for resident . (16) Multi-tiered system of supports The term multi-tiered system of supports means a comprehensive continuum of evidence-based, systemic practices to support a rapid response to the needs of students, with regular observation to facilitate data-based instructional decision making. (17) Out-of-school suspension The term out-of-school suspension means an instance in