Understanding the importance of functionally equivalent replacement behaviours in special education

Christine Reeve highlights the critical need for support plans to focus on behaviours’ functions rather than their appearances, emphasising that effective replacement behaviours must serve the same purpose as challenging actions to improve outcomes for children with special behavioural needs.

Replacement behaviours often sound straightforward until a child is throwing chairs and “use your words” is clearly not enough. Christine Reeve, who has worked for decades in special education and behaviour analysis, argues that many support plans fail because teams choose a substitute behaviour by looking at what the child does, rather than at what the behaviour achieves.

The key idea is simple: a replacement behaviour must serve the same function as the challenging behaviour. In other words, it should help the child get the same outcome in a more acceptable way. If a child lashes out to escape a task, the replacement skill has to provide a safe way to ask for a break or for help. That logic aligns with the broader guidance from state education agencies, which say functional behavioural assessment is designed to identify why a behaviour is happening so schools can build effective supports around it.

Reeve makes the case that there is no single replacement for hitting, spitting or screaming. The right skill depends on whether the behaviour is driven by escape, attention, access to something tangible or automatic reinforcement, meaning the behaviour itself is providing the reward. A child who spits to avoid work may need to request a pause, while a child who spits to get adult attention may need to learn how to call for help in a way that reliably gets a response. Special education guidance from Arizona, Minnesota and Missouri all stresses that the point of an FBA is to understand the function of the behaviour, not just its appearance.

That distinction matters because a replacement only works if it is functionally equivalent. Reeve points to research by Carr and Durand showing that teaching a communication skill that does not match the function of the problem behaviour does not reduce the behaviour. If the child is trying to escape a demand, asking for attention will not solve the problem. The new skill has to produce the same result, and it also has to be easier, faster and more reliable than the challenging behaviour, according to the work Reeve cites from Horner and Day.

There are limits, though. Reeve notes that some automatic or sensory behaviours are harder to replace because the reinforcer is internal rather than social. In those cases, schools may need to look for another activity or input that offers similar sensory feedback, or use strategies that reduce anxiety or keep the hands and body occupied. The form of the behaviour can offer a clue, but only after the function has been established through assessment.

The practical lesson for parents and educators is that replacement behaviours are not slogans or reminders. They are taught skills, chosen because they do the same job as the problem behaviour and then reinforced every time at first. Reeve’s broader message is that behaviour support works best when adults stop asking, “What should we replace this with?” and start asking, “What is this behaviour doing for the child?” That is the question an FBA is meant to answer.