Various neuropsychiatric disorders are a common feature today, not least in educational contexts where Attention Deficit Hyperactivity Disorder (ADHD) is a common diagnosis. The dominant perspective regarding ADHD is biomedical. This perspective has been questioned and challenged in various ways. The aim of this article is to think ADHD through quantum physicist and philosopher Karen Barad's [Barad, K. 2007. "Meeting the Universe Halfway: Quantum Physics and the Entanglement of Matter and Meaning." Durham, NC: Duke University Press.] theory of agential realism. According to Barad, what we perceive as singular entities do not exist in advance. Barad pays attention to the world's entanglements, and what we perceive as singular objects and subjects are effects of specific and various material-discursive practices acting as agential cuts. The theory of agential realism assigns performativity to matter, which highlights that ADHD is something that continuously comes into being together with human and non-human bodies. The material dimension has not previously been emphasised as a causal factor in studies on ADHD. In this article, the focus is on the agency of the book. As a conclusion, the importance of taking responsibility for every material-discursive practice with which we are always entangled is emphasised.