(105 ILCS 5/11E-30)
    Sec. 11E-30. Partial elementary unit district formation.
    (a) One or more entire high school districts and one or more entire unit districts, all of which are contiguous, may be organized into a combined high school - unit district as provided in this Article. The combined high school - unit district shall serve all residents of the district for high school purposes and those residents residing in the portion of the territory included within the boundaries of the dissolved unit district or districts for elementary purposes.
    (b) One or more contiguous unit districts may, as provided in this Article, dissolve and form a single new combined high school - unit district and one or more new elementary districts. The boundaries of the new elementary district or districts shall be based upon the boundaries of the dissolved unit district or districts electing to join the combined high school - unit district only for high school purposes. Territory included within the boundaries of the new elementary district or districts shall be served by the new combined high school - unit district only for high school purposes. All other territory within the combined high school - unit district shall be served by the combined high school - unit district for both high school and elementary purposes.
    (c) A high school district and 2 or more elementary districts that collectively are substantially coterminous may seek to organize into an optional elementary unit district as provided in this Article, provided that territory comprising at least 51% of the equalized assessed valuation of the high school district is subject to a combined high school and elementary maximum annual authorized tax rate for educational purposes of 4.0% or less. The optional elementary unit district shall serve all residents of the district for high school purposes. The optional elementary unit district shall serve residents of only those elementary districts electing to join the optional elementary unit district, as determined in accordance with subsection (b) of Section 11E-65 of this Code, for elementary purposes. The corporate existence of any elementary district electing not to join the optional elementary unit district in accordance with subsection (b) of Section 11E-65 of this Code shall not be affected by the formation of an optional elementary unit district, and an elementary district electing not to join the optional elementary unit district shall continue to serve residents of the district for elementary purposes.
    (d)(1) For 5 years following the formation of an optional elementary unit district, any elementary district that elected not to join an optional elementary unit district for elementary purposes may elect to dissolve and combine with the optional elementary unit district by filing a petition that requests the submission of the proposition at a regularly scheduled election for the purpose of voting for or against joining the optional elementary unit district and that complies with the other provisions of this Article.
        (2) After an election in which an elementary district
    
votes to join an optional elementary unit district in accordance with paragraph (1) of this subsection (d), but prior to the dissolution of the elementary district, the elementary district must first issue funding bonds pursuant to Sections 19-8 and 19-9 of this Code to liquidate any operational deficit or debt incurred or accumulated since the date of the election in which the proposition to form the optional elementary unit district passed. The elementary district shall not be required to comply with the backdoor referenda provisions of Section 19-9 of this Code as a condition of issuing the funding bonds. If applicable, the tax levy to pay the debt service on the funding bonds shall not be included in the district's aggregate extension base under Section 18-210 of the Property Tax Code. Taxes levied to repay principal and interest on any long term debt incurred or accumulated between the date of the election in which the proposition to form the optional elementary unit district passed and the date of the elementary district's dissolution and joining the optional elementary unit district in accordance with paragraph (1) of this subsection (d) shall be levied and extended only against the territory of the elementary district as it existed prior to dissolution.
        (3) If all eligible elementary districts elect to
    
join an optional elementary unit district in accordance with this subsection (d), the optional elementary unit district shall thereafter be deemed a unit district for all purposes of this Code.
(Source: P.A. 94-1019, eff. 7-10-06.)