D.C. Code § 38-1922
The Board of Education of the District of Columbia is authorized to pay the full salary of the educational employee of said Board during the time such employee is performing teaching duties in a foreign country under such exchange program, in the same manner and to the same extent as if such educational employee were actually performing his teaching duties in his regularly assigned position in the public schools of the District of Columbia, and any such educational employee participating in such program shall, for purposes of promotion, computation of annual increment, computation of service for pension credit, including salary contributions to the pension fund, and leave of absence credits, be considered as performing teaching duties in the schools of the District of Columbia.
D.C. Code § 38-1922