Many undergraduate students struggle to engage with higher order skills such as evaluation and synthesis in written assignments, either because they do not understand that these are the aim of written assessment or because these critical thinking skills require more effort than writing a descriptive essay. Here, we report that students who attended a freely available workshop, in which they were coached to pose a question in the title of their assignment and then use their essay to answer that question, obtained higher marks for their essay than those who did not attend. We demonstrate that this is not a result of latent academic ability amongst students who chose to attend our workshops and suggest this increase in marks was a result of greater engagement with 'critical thinking' skills, which are essential for upper 2:1 and 1 class grades. The tutoring method we used holds two particular advantages: First, we allow students to pick their own topics of interest, which increases ownership of learning, which is associated with motivation and engagement in 'difficult' tasks. Second, this method integrates the development of 'inquisitiveness' and critical thinking into subject specific learning, which is thought to be more productive than trying to develop these skills in isolation.