Iowa's House File 428 would, if enacted, revert the state's science standards to "the science standards utilized by school districts in this state during the 2014-2015 school year" — just before the state adopted the Next Generation Science Standards. The bill was introduced on February 19, 2019, and referred to the House Education Committee.
The lead sponsor of HF 428 is Sandy Salmon (R-District 63). In 2015, Salmon introduced a bill, House File 272, which would have prevented Iowa from adopting the NGSS, in part because they "present evolution as scientific fact and shine a negative light on human impacts on climate change," according to the Cedar Rapids Gazette (March 2, 2015).
After HF 272 died and the NGSS were adopted in 2015, Salmon filed a series of bills — HF 2054 in 2016, HF 140 in 2017, and HF 2317 in 2018 — aimed at reversing the adoption of the standards and prohibiting the state from requiring their use. None of these bills succeeded.
In addition to undoing the adoption of the NGSS, Salmon's new bill, HF 428, would also prevent the state from requiring adoption of the state science standards or the use of specific instructional materials and would require further revisions to the state science standards to be approved by the legislature and governor.
Also currently with the House Education Committee is House File 61, which would prohibit the state from requiring the use of the NGSS. Its sponsor, Skyler Wheeler (R-District 4), is on record as opposing the NGSS on account of their inclusion of climate change and evolution; he is also a cosponsor of HF 428.