What is the climax of the witches?

Well, honey, the climax of "The Witches" by Roald Dahl is when the Grand High Witch's plan to turn all the children into mice is foiled by the young protagonist and his grandmother. It's the moment when everything hits the fan and the tension reaches its peak before the resolution kicks in. So, buckle up, because that's where the real magic happens in this wickedly delightful tale.