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Functional Behavioral Assessments 101

Functional Behavioral Assessments 101

Published: Nov. 23, 2021Updated: Mar. 5, 2024

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A Functional Behavioral Assessment (FBA) is a process that helps everyone on the IEP team stop, take a breath, and listen to what kids are trying to say with their behavior. While an FBA can be quite useful in helping to determine how children can replace difficult behaviors with more positive or functional ones, this type of assessment can also come with its own set of questions for parents.

We reached out to special education attorney Meira Amster as well as Faye Carter (PhD, BCBA-D), regional director of ABA Services for STAR of CA, to talk through how to request an FBA, how it should be conducted, and how you can make sure it benefits your child.

When and why to conduct an FBA

According to the California Department of Education (CDE), while not legally defined by any federal law or regulation, an FBA is “understood to be an evaluation under the IDEA” that is conducted by a public agency “to assist in determining whether a child is, or continues to be, a child with a disability and/or to determine the nature and extent of the special education and related services that the child needs, including the need for a BIP [behavioral intervention plan].”

FBAs can be conducted when the IEP team determines it would be appropriate for the child, or when a change in placement is being sought due to behaviors. According to the CDE, Local Education Agencies (LEAs) are required to conduct an FBA “when a change in placement is being sought because of a behavior that has violated the school’s code of conduct, and the IEP team has found that the behavior relates to the child’s disability, and the LEA had not conducted an FBA prior to such determination before the behavior that resulted in the change of placement.” According to attorney Meira Amster, the code of conduct violation is the kicker needed for the district to be legally responsible for funding an FBA. However, the good news is that FBAs and subsequent BIPs happen much more frequently in practice than required by law — and in practice, a school district will often want to conduct an FBA when a behavior gets in the way of learning. “If an FBA is requested, typically the district will conduct one,” Amster explains.

When is a functional behavioral assessment conducted?

An FBA is also sometimes conducted when seeking a 1:1 aide for your child. “Often, I have a client coming out of a special education Pre-K classroom, and we know we want a GenEd placement for kindergarten,” Amster says. “I request that an FBA be conducted at the end of the Pre-K year so that they can offer an aide in that IEP for kindergarten.” The FBA will likely accompany a Special Circumstance Instruction Assistance (SCIA) assessment, which you can learn more about in our article on 1:1 aides.

Keep in mind that not only does an FBA identify behaviors, it can also show the absence of them.

Once an FBA is requested, the district has fifteen days to provide you with an assessment plan. Once that is signed and returned, the district then has sixty days to conduct the FBA and hold an IEP meeting to discuss it. If you are not satisfied with the FBA, you can request an Independent Educational Evaluation (IEE).

Who conducts a functional behavioral assessment and how

Ideally, a Board Certified Behavior Analyst (BCBA) would conduct the FBA, but that’s not always the case. It can be performed by anyone trained and knowledgeable, such as a teacher, school psychologist, a Registered Behavior Technician (RBT), or a Board Certified Assistant Behavior Analyst (BCaBA). While a parent can always make a request for the person they feel is the most appropriate to do the assessment (and the IEP team does need to consider proper credentials in choosing), parents ultimately do not have control over who conducts the FBA.

Once the professional has been identified, they will first define the behavior in question and then use what is known as the “ABC” approach to properly analyze it.

  • A is for Antecedent

    • This examines what is triggering the behavior, or what might come just before it. You also need to examine the bigger picture, Faye Carter says. “Is it always occurring at this time of day, under these circumstances, or under bright lights, for example?”
  • B is for Behavior

    • According to Carter, the actual behavior needs to be looked at from all sorts of angles, such as intensity and frequency. “What does the topography look like? How frequently is it occurring? That way, during the intervention phase, you can measure a decrease or any changes,” she explains.
  • C is for Consequence

    • A consequence is not a punishment but rather whatever maintains the behavior. What reinforces it? “If a child receives attention in class from the teacher by calling out, that attention is the consequence reinforcing the calling out,” Carter says.
  • H is for Hypothesis

    • Once you determine when the behavior is most likely to occur — such as when a teacher is asking questions and the child doesn’t want to wait their turn, or perhaps the child can’t tolerate independent work, so they stimulate themselves by getting attention at that time — you look at the response given. Are peers laughing in response to something funny the child says? Does the teacher give an immediate acknowledgement of “Good job” if the child’s answer is appropriate, or do they respond with a “negative” response by telling the child to stop talking?

    • The next step is to play with that response. “You’re determining your hypothesis,” says Carter. “For example, you ask the teacher to please remove attention during this routine and then see what happens.”

What is a behavioral intervention plan (BIP)?

In this clip, Undivided's Education Advocate Lisa Carey explains the difference between an FBA and a BIP:

“Once you’ve got a pretty good idea of when a behavior will occur, you can look at all the factors from your assessment and create an intervention,” Carter explains. The behavioral intervention plan can use an Antecedent strategy by asking the teacher to proactively give that student more attention, for instance with a class job that can occupy them and lessen the likelihood of the behavior recurring.

A Behavior strategy will redirect the actual behavior by teaching the child how to request attention in a more socially appropriate way, such as by asking politely or raising their hand.

And finally, using a Consequence strategy has the teacher responding immediately whenever the child raises their hand in order to reinforce that more appropriate behavior. Or conversely, a teacher may use a “planned ignore” approach whenever the child calls out. The teacher could also utilize a cue system, like a picture, to remind the child to raise their hand.

What to watch for during an FBA

The CDE puts it this way: “No state or federal law or regulation defines a functional behavioral assessment.” It’s a loaded statement, and it can leave a lot open to interpretation. Amster has offered a few suggestions on where to point your magnifying glass when reviewing your child’s FBA.

  • Make sure the “behavior” is properly defined. “Because if you don’t, then your data won’t make any sense,” she says. “Let’s say we’re looking at a student who’s ‘flopping’ on the ground. The FBA defines the behavior as ‘whenever the student is walking and falls on the ground for more than five seconds.’ Well, what if the kid is sitting in a chair and just flops on the ground? That wouldn’t be part of the data, but it’s something you’d also want to stop. You’d also want to define ‘flopping.’”

  • Make sure the behavior chart you receive illustrates the data they claim it does. “Sometimes, charts don’t measure what they say they do. Does it show behaviors per day, per hour, per minute? Have they interviewed the teacher and gotten their concerns? Have they interviewed the parents? That’s something I’m looking for on all assessments,” Amster explains.

  • Make sure the intervention matches the behavior. Carter explains, “Moving a child to the front of the room when they are seeking attention may work, but if the child is engaging in self-stimulatory behavior, where they are in the classroom may not make a difference.”

  • Make sure any resulting goals are properly written, measurable, and achievable!

  • If you have one, be sure to include the supervisor of your in-home ABA therapy in any discussions surrounding an FBA. “Their voice holds a lot of weight with the district, and they have the expertise to look at the school-conducted FBA and see if there are any issues,” Amster says.

What to do if your request for an FBA is refused

The school must give you prior written notice, and just as with all disputed assessments, you can respond by filing for due process or mediation. Amster reports that there are also a variety of alternative dispute resolution possibilities offered by all school districts. Parents always have the option to get an FBA done privately, on their own dime, and the school district has to not only allow the assessor onto campus to conduct the observation, but also consider the completed assessment.


Make sure the BIP is followed by everyone your child works with. Remember: If a behavior is reinforced inappropriately even once, it can undo weeks or even months of hard work!



When and why to conduct an FBA

Who conducts a functional behavioral assessment and how

What is a behavioral intervention plan (BIP)?

What to watch for during an FBA

What to do if your request for an FBA is refused


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AnnMarie MartinUndivided Writer

Reviewed by Jennifer Drew, Undivided Senior Editor #### Contributors Lisa Carey, Undivided Education Advocate Dr. Faye Carter, BCBA-D, Regional Director of ABA services for STAR of CA Lisa Carey, Undivided Education Advocate Meira Amster, Special education attorney

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