For decades, scholars have advocated for critical perspectives in Physical Education (PE), encouraging more creative and inclusive ways of thinking about and doing PE. Unfortunately, this critical work has had limited impact on how PE is conceptualised -- within curricula or by teachers -- both in the United Kingdom (UK) and internationally. As such, there is a pressing need to consider how we might advance this agenda. Working with PE teachers from across the four home nation of the UK (England, Northern Ireland, Scotland and Wales), we organised a series of workshops to enable PE teachers from across these contexts to reflect on and discuss their respective curricula. This novel approach -- of engaging in cross-border dialogue -- was found to have potential for fostering critical thinking around PE curricula. Indeed, teachers were supported to begin thinking more critically through learning about other curriculum contexts and considering alternative possibilities for PE and their learners -- though persistent challenges around blocks of activity and teaching games were acknowledged. We argue that these teachers are on the (challenging) journey of becoming critical, but time and support is necessary to interrogate prevailing discourses in PE and allow new ways of thinking to emerge.