Ala. Const. § 37-10.21
In addition to any taxes now authorized or that may hereafter be authorized by the Constitution and laws of Alabama, the several school districts of Jefferson county shall, subject to an election in each such school district as hereinafter provided, have power to levy and collect a special district tax of not exceeding fifty (50) cents on each one hundred dollars ($100) of taxable property in such district for the furtherance of education therein. A school district within the meaning of this section shall include (a) that part of Jefferson county outside of the municipalities of Birmingham, Bessemer, Fairfield, Tarrant city and Mountain Brook as one district, except that the Jefferson county board of education is authorized and empowered to designate any part or portion of said district as a separate school district., (b) the city of Birmingham as one district, (c) the city of Bessemer as one district, (d) the city of Fairfield as one district, (e) the city of Tarrant City as one district, and (f) the city of Mountain Brook as one district. No tax shall be levied hereunder unless the rate of such tax, the time such tax is to continue and the purpose thereof shall have been first submitted to the vote of the qualified electors in each such district and voted for by a majority of those voting at such election. Any election on any such district tax shall be called and held, the results declared, and the tax levied and collected in the same manner as now or hereafter provided by law in the case of school district taxes authorized by Sections 269.01 through 269.03, except that no county-wide tax shall be required as a condition precedent for a district tax under this amendment. The holding of one election shall not preclude a later election in the same district but no election in a district shall be held within two years from the date of the last election held in such district under the authority of this amendment. The proceeds of any special district tax authorized by this amendment shall be expended for the support of education only in the special district or separate district in which the tax is levied.