Ron confronts Cho Chang about the Tutshill Tornados, after which Hermione tells him off (OP12). From this point on, Hermione tends to drag Ron out of the way when Cho wants to talk with Harry.
Harry is given a week’s worth of detentions by Umbridge and a biscuit by McGonagall (OP12).
Hermione stops most of Fred and George’s testing by putting them on notice that she’ll report them to their mother otherwise. She also starts planting clothes in Gryffindor Tower for house-elves (OP13).