; (2) by striking January 1, 2018 and inserting January 1, 2022 ; (3) by striking December 31, 2017, shall and inserting December 31, 2021, shall ; and (4) by adding at the end the following: For purposes of this section, in the case of State or local taxes with respect to any real or personal property paid during a taxable year beginning in 2020 or 2021, the Secretary shall prescribe rules which treat all or a portion of such taxes as paid in a taxable year or years other than the taxable year in which actually paid as necessary or appropriate to prevent the avoidance of the limitations of this subsection. . (c) Effective date The amendments made by this section shall apply to taxes paid or accrued in taxable years beginning after December 31, 2019. 4. Increase in deduction for certain expenses of elementary and secondary school teachers (a) Increase Section 62(a)(2)(D) of the Internal Revenue Code of 1986 is amended by striking $250 and inserting $1,000 . (b) Conforming amendments Section 62(d)(3) of the Internal Revenue Code of 1986 is amended— (1) by striking 2015 and inserting 2019 ; (2) by striking $250 and inserting $1,000 ; and (3) in subparagraph (B), by striking 2014 and inserting 2018 . (c) Effective date The amendments made by this section shall apply to taxable years beginning after December 31, 2018. 5. Above-the-line deduction allowed for certain expenses of first responders (a) In general Section 62(a)(2) of the Internal Revenue Code of 1986 is amended by adding at the end the following new subparagraph: (F) Certain expenses of first responders The deductions allowed by section 162 which consist of expenses, not in excess of $1,000, paid or incurred by a first responder— (i) as tuition or fees for the participation of the first responder in professional development courses related to service as a first responder