DENVER, Colo. -

At least one Denver school is making attendance for students optional on Thursday due to the heat, and it plans to be closed Friday with high temperatures once again predicted to be in the 90s.

The Downtown Denver Expeditionary School said on its website that students whose parents decide to have them stay home Thursday will have an excused absence. The charter school says it will be completely closed Friday.           

Denver Public Schools has dozens of buildings without air conditioning. Some schools were built more than 100 years ago.