When the girls are playing terror tag, Dawn Undercover of the red team screams twice. The blue team only got one point. The other point never went up.
At times you can tell they are using a green screen effect for the flying that the cast does and Miss Spellbinder when she is conducting a flying class when the group have got their kittens and learning to fly. Also when Mildred has turned the bad witches into snails in the TV version of the film they had squeaky voices dubbed for the snails but in the film if you watch the same scene when Mildred, Miss Cackle and Miss Hardbroom are talking to the snails the squeaky voices are not there! Just silence.
When Mildred and Maud have reappeared and are sitting talking, when Mildred says, "If I live to have any," the actress playing Maud is mouthing the line as Mildred says it.