Behavior hypothesis statement examples

By the IEP Atlas editorial teamLast updated November 1, 2026

Short answer

A strong FBA hypothesis statement names the setting event, the trigger, the behavior and one function, in that order. Example: when Lia has slept poorly and is given a writing task longer than one paragraph, she tears her paper to escape the task. Each part should match counts in the ABC data, so the team can test it.

A hypothesis statement is the one sentence an FBA exists to produce. Everything in the behavior plan hangs on it: the prevention steps, the replacement behavior, and how adults respond. A vague hypothesis gives you a vague plan.

Every example below shows the statement, the data that supports it, and the feature that makes it strong. The students and numbers are fictional. For the full assessment process, see how to conduct an FBA; for where the hypothesis fits in the whole cycle, see the FBA and BIP guide.

The four-part frame

Use the same frame every time:

When (setting event, if one shows up in the data) and (immediate trigger), the student (observable behavior) to (get or avoid something).

Part	What it answers	Where it comes from
Setting event	What makes the behavior more likely today?	Interviews, health notes, daily logs
Antecedent	What happens right before?	ABC data, scatterplot
Behavior	What does it look like?	The operational definition
Function	What does the student get or avoid?	Consequence counts, hypothesis test

The setting event is optional. Leave it out when nothing in the data points to one. Never leave out the function.

Attention-maintained hypothesis examples

#	Hypothesis	Data behind it	What makes it strong
1	When the teacher works with a small group and has not spoken to Mateo for 5 minutes, he calls out jokes to get adult attention.	19 of 24 call-outs during small-group time; teacher responded in 21 of 24.	Gives a time threshold the plan can beat with check-ins.
2	When peers start partner work and Ava has no assigned partner, she pokes classmates to get peer attention.	12 of 15 incidents in unstructured pairing; peers reacted in 14.	Names peer attention, not adult attention.
3	On Mondays after weekends at his dad's house, and when the aide moves to another student, Leo cries loudly to get adult attention.	8 of 11 episodes on Mondays; parent reports a weekend schedule change.	The setting event comes from parent interview data.
4	When an adult praises another student nearby, Zoe throws her pencil to get the adult to look at her.	9 of 10 throws within 30 seconds of praise to a peer.	Ties the trigger to a short, measurable time window.
5	During transitions in the hallway, when adults walk at the front of the line, Kai lies on the floor to get adult attention.	7 of 8 episodes when no adult was near the back of the line.	Points to a prevention step: move an adult to the back.
6	When Rosa finishes work early and no new task is given, she sings loudly to get peer laughter.	11 of 13 episodes after early finishing; peers laughed in 10.	Separates "nothing to do" from "work is hard."

Escape-maintained hypothesis examples

#	Hypothesis	Data behind it	What makes it strong
7	When Lia has slept poorly and is given a writing task longer than one paragraph, she tears her paper to escape the task.	10 of 12 episodes on days the parent logged under 7 hours of sleep.	A setting event with a number the family can track.
8	When given an independent worksheet with 20 or more problems, Jonah leaves the classroom to escape the task.	14 of 18 exits during long worksheets; work not made up in 13.	Names the task size, which the plan can change.
9	When asked to read aloud in front of the class, Sam puts his head down and refuses to answer to avoid reading aloud.	6 of 6 episodes during whole-class read-aloud; none in 1:1 reading.	The contrast with 1:1 rules out general task escape.
10	When the classroom gets loud during centers, Nia covers her ears and runs to the hallway to escape the noise.	9 of 11 episodes in centers; sound meter readings over 75 decibels in 8.	Escape from a setting, not a task, with a measured trigger.
11	When told to stop computer time and start math, Eli argues and kicks the desk to delay the transition.	15 of 17 episodes at the computer to math switch.	Escape from the next task, which differs from item access.
12	When Grace is corrected in front of peers, she swears at the adult and is sent out, escaping the class.	7 of 9 episodes after public correction; sent out in 7.	Shows how removal reinforces the behavior.

Hypothesis examples for getting an item or activity

#	Hypothesis	Data behind it	What makes it strong
13	When a peer has the red tablet case Omar prefers, he grabs it to get the tablet.	8 of 9 grabs target the same tablet; he keeps it in 6.	Specific item, so the plan can teach asking and waiting.
14	When recess ends while a game is still going, Ana hits the ball away from peers to keep playing.	6 of 7 episodes at the end of recess games.	Separates "more time" from escape from class.
15	When the snack bin is in view and snack time is more than 10 minutes away, Theo screams to get a snack.	12 of 14 episodes with the bin visible.	Gives a visible trigger the team can remove.
16	When told "no" to a second turn on the swing, Ivy drops to the ground to get another turn.	9 of 10 episodes after a denied turn; adult gave the turn in 5.	Shows intermittent reinforcement, which keeps it strong.
17	When his phone is collected at the start of class, Marcus refuses to hand it over to keep using it.	11 of 12 refusals at phone collection.	A single, predictable trigger with a clear item.
18	When free choice is announced and the art bin is taken, Mia knocks over the block tower to get the art materials.	5 of 6 episodes when the art bin was in use.	Ties the behavior to one wanted activity.

Sensory or automatic hypothesis examples

#	Hypothesis	Data behind it	What makes it strong
19	During long seated lessons with little movement, Ben rocks his chair onto two legs, which produces movement input.	Occurs across subjects and adults, alone or with others; 3 times as often in lessons over 30 minutes.	Rules out social functions by showing it happens alone.
20	When there is no item in her hands during waiting times, Lucy bites the edge of her sleeve, which produces oral input.	Happens with and without adults present; stops when she holds a chew tool.	The quick stop with an alternate input supports the function.
21	In quiet independent work, Owen hums continuously, which appears to produce auditory input.	Occurs at the same rate whether adults respond or ignore it.	Consequence counts show attention does not change it.
22	When seated near the window with bright light, Ella flicks her fingers in front of her eyes, which produces visual input.	16 of 18 episodes in the window seat.	Names a setting the team can test by moving her seat.
23	When waiting in line with nothing to do, Jamal pushes his palms hard against the wall, which produces pressure input.	10 of 11 episodes during waits over 2 minutes.	Gives a duration the plan can shorten or fill.
24	Across settings and times, Ruby picks at her skin, with no change in rate when alone or with adults.	Same median rate in 4 observation settings.	States the evidence for automatic function plainly.

Sensory hypotheses need the most evidence, because "sensory" is often a guess when the team has not looked at consequences. Show that the behavior continues when nobody responds and when nothing is removed.

Weak and strong versions side by side

Each weak version below fails for a reason the data could have fixed.

Weak	Problem	Strong, tied to the data
Carlos is noncompliant because he does not want to work.	Label, no trigger, no behavior	When given a multi-step math word problem, Carlos pushes the paper off his desk to escape the task (11 of 13 episodes).
Mia acts out for attention and escape.	Two functions, vague behavior	When the teacher leaves her table and 4 minutes pass, Mia slaps the table to get adult attention (15 of 18 episodes).
Tyler has meltdowns because of his autism.	Diagnosis is not a function	When a planned activity changes without warning, Tyler screams and drops to the floor to delay the new activity (7 of 8 changes).
Ana is sensory seeking.	No setting, no evidence	When seated for more than 20 minutes, Ana stands and spins near her desk, with no change when adults respond (same rate in 5 settings).
Owen is defiant with substitutes.	Label, no behavior	When a substitute gives directions, Owen walks away and sits in the reading corner to avoid the task (6 of 7 sub days).

The fix is the same each time: replace the label with the operational definition, add the trigger, and pick one function that the counts support. The guide to operational definitions of behavior helps with the behavior part, and how to take ABC data explains how to get the counts.

Checking a hypothesis before you write the plan

A hypothesis is a claim the team can test. Make one planned change that should work if the function is right, and keep counting for a week.

Attention: add scheduled check-ins. If the behavior drops, the hypothesis holds.
Escape: shorten or chunk the task, or add a break option. Watch the count.
Item or activity: give a warning and a timer, or teach a "first, then" routine.
Sensory: offer a matched input on a schedule and see whether the behavior falls.

If the count does not move, go back to the ABC data before writing the BIP. Record the test and its result in the report; the FBA template has a section for it.

From hypothesis to goal

The function picks the replacement behavior, and the replacement behavior becomes the IEP goal. For example 8, the replacement is a break request: "During independent math, Jonah will request a break with his card and return within 3 minutes in 4 of 5 opportunities across 3 weeks." The steps are in writing a behavior goal from an FBA, and the replacement behavior goal templates have more wording. Paste your draft into the goal checker to catch vague parts.

The What Works Clearinghouse practice guide on classroom behavior recommends identifying the conditions that prompt and reinforce a behavior before choosing a strategy.^[1] The IRIS Center FBA module includes practice in writing hypothesis statements from sample data.^[2]

Printable version

Print this page or copy the frame below onto a single sheet for your FBA folder. No sign-up is needed.

When (setting event): ________
And (antecedent): ________
The student (behavior): ________
To (get or avoid): ________
Supporting counts: ___ of ___ episodes
Test planned: ________ Result: ________

Before you finalize, check four things. Is there one function? Does every part match a count? Would a new staff member recognize the behavior? Does the plan you have in mind address that function?

Frequently asked questions

Can a hypothesis statement have two functions?

Write one hypothesis per function. If the data truly show a behavior serving two functions in different settings, write two statements, each with its own trigger and supporting counts. One sentence naming two functions usually means the analysis is not finished.

What is the difference between a setting event and an antecedent?

An antecedent happens right before the behavior, such as a worksheet being handed out. A setting event is an earlier condition that makes the behavior more likely, such as poor sleep or a missed breakfast. Include the setting event only when the data show one.

How many ABC observations do I need before writing the hypothesis?

Enough for a clear pattern, which for most school FBAs means at least 10 to 15 recorded episodes across several days and settings. If the counts are split evenly across antecedents, collect more before you commit to a function.

Use it in IEP Atlas

Sources

Reducing Behavior Problems in the Elementary School Classroom, What Works Clearinghouse, Institute of Education Sciences
Functional Behavioral Assessment: Identifying the Reasons for Problem Behavior and Developing a Behavior Plan, IRIS Center, Vanderbilt University

Written and checked by the IEP Atlas editorial team under our editorial policy. This guide describes general practice and federal rules. It is not legal advice; your state may add requirements, and the IEP team makes the decisions for each student.