Other mistake: The time on Miss Trunchbull's mantel clock is 7:45. Matilda uses her power to move the hands to 9:00 and the clock begins chiming. It should have also chimed when the hands reached 8:00. Matilda then moves the hands to 11:00. The clock begins chiming 11 but failed to chime when the hands reached 10:00.
Steven LeeSuggested correction: We have a grandfather clock and if you spin the hands past an hour mark quickly you hear the click like it wants to play the hourly tune but then doesn't. It only plays if you go just past the hour and stop. Trunchbull's clock may be similar.
jimba