(a) A town shall constitute a school district, except that when a town contains an incorporated school district, the town school district shall consist of that part of the town not embraced within the incorporated school district.
(b) It is the policy of the State to support two or more school districts within a supervisory union in establishing a unified union district in accordance with section 722 of this title, if such unified union district would then be large enough to qualify for designation by the State Board as a supervisory district.