An affidavit filed with the case says Hailey Smart was having sexual relations with a student during the 2017-2018 school year. ... The affidavit stated the two had sex in the classroom multiple times after class. Smart is also accused of having sex with him at his house during the teacher walkout.The British press has the story here. This sort of behavior during a teacher walkout (a Clinton teacher reportedly confessed to the same thing) strikes me as wildly inappropriate.
[Update: One of the chief ringleaders of the 2018 teacher walkouts in Oklahoma has been arrested for lewd proposals to a minor, the Stillwater Police Department announced on May 20, 2020.]