This case study was undertaken to characterise the interventions made by a kindergarten teacher during a multiplicative structure problem-solving lesson. The study findings show that when she realised the children were having difficulty, she provided assistance to enable them to find the right answer. When the children gave an incorrect response, she did not prompt them to reason their ideas, but either ignored their response or guided them to the right answer with manipulatives. Moreover, less varied and simpler problem-solving strategies were employed when the teacher gave instructions than when she gave help or clues. From this, we conclude that the intervention determined the type of strategy used by the children and the teacher varied their discourse depending on the children's performance.