Whenever the Board of Educational Lands and Funds determines, considering all relevant factors, that it would be in the best interests of the educational trust to do so, it may subdivide and plat any tract prior to offering it for sale. Such plats shall be prepared as prescribed in section 72-259.02 and shall be filed in the office of the register of deeds and such filing shall constitute a dedication of the streets and alleys shown therein so long as the same are used for such purposes.