Well structured, and the instruction on not putting a hand behind them for fear of harm is well said, particularly if a cane was being used: broken fingers could occur, with the possibility of a damages lawsuit, irrespective of accidental injury.
Just for once "panties down" is interpreted as "panties off". As it should be. Also the teacher gave instructions "forearms on the desk" but only two girls did as they were told. Extra spanks for them (in my opinion).