The board, by the adoption of rules, shall give priority in allocating funds to districts which will benefit most from the reconstruction or replacement of schoolhouse facilities. This priority may be based on the age and structural safety of existing buildings at the school or schools where the construction or reconstruction will occur, acuteness of overcrowding and density of population in the attendance areas affected, or any other factors that will insure that the greatest need will be served in allocating funds under this article.