Task analysis and chaining in ABA

In short

One concrete example runs through this whole article: teaching a child to wash their hands.
A task analysis is the list of steps the activity takes for this particular child — not the list a manual prints. Write it by doing the routine yourself, slowly, noting each action separately.
Steps are the right size when the child can attempt a whole one, with help or without — not necessarily independently yet. Too coarse and every step is a wall; too fine and the routine never feels like one activity.
Three ways to chain: forward, backward, and total task. They differ in where the child’s success lands, not in how hard they are.
Backward chaining teaches the last step first, so every practice run ends on the step the child is working toward — even if that step still needs help at the start.
Before teaching a chain, take a baseline: run it once, help where needed, and write down which steps were already independent. You will teach fewer steps than you thought.

Washing hands is one thing to an adult and about eleven things to a child learning it. Task analysis is the unglamorous work of writing down which eleven, and chaining is how you teach them so they end up feeling like one activity again.

Both are old, plain and reliable, and both are usually done badly in the same way: the step list is copied from somewhere instead of observed.

Writing the step list

Do the routine yourself, slowly, and write down each action separately. Not what you would say — what you do. Then watch the child attempt it and adjust: a step they sail through can be merged with its neighbor, a step where they stall probably contains two steps.

That is the whole method, and it is why two children learning the same routine can legitimately have different lists. Handwashing might be six steps for one child and twelve for another. The list belongs to the child, not to the skill.

One useful check: could a stranger follow your list and produce the routine, without guessing? If a step says “wash hands properly”, it is not a step yet.

What a list written this way looks like

Handwashing, for a three-year-old who reaches the sink on a step stool:

Climb onto the stool.
Turn on the tap.
Wet both hands.
Pick up the soap.
Rub the palms together.
Rub the back of each hand.
Rub between the fingers.
Put the soap down.
Rinse both hands.
Turn off the tap.
Dry with the towel.

This list is an example, not a template. For a child who needs no stool it is ten steps; for a child who does not yet separate rubbing from rinsing, “rub the palms” and “rub the back of each hand” are one step while they learn it, and “rinse both hands” is two. The test is not whether your list resembles this one — it is whether every line names an action the child can attempt.

The three chains

Forward chaining. Teach step 1 to independence, prompting the rest through. Then steps 1-2. And so on. The child’s independent work sits at the beginning of the routine.

Backward chaining. Prompt every step through except the last, which is the one being taught — it can still need help at first, and its prompt fades the same way as any other step’s. Then the last two. And so on backwards. The child’s independent work grows from the end, which means every practice run finishes on the step being taught, immediately followed by the natural payoff of having finished.

Total task. Run the whole routine every time, prompting whichever steps still need it and fading each one separately. Nothing is postponed; the child gets the shape of the whole routine from the start.

None of the three is the advanced one, and picking one is less about the task’s shape than about what the baseline below shows for this particular child. Total task suits a child who can already do several of the steps; backward suits a routine with a clear reward at the end (getting the shoe on, eating the sandwich), for a child who tolerates being prompted through the earlier steps; forward suits a routine where the early steps are the hard ones and the end is trivial.

Figure — One routine, three ways to teach it

Steps: pick up → fill → water → put away
Forward: begin with the first step and add later steps; assist or complete the remaining steps as needed.
Backward: assist or complete the initial steps and teach the last step first, then add earlier steps.
Total task: offer practice in every step and help where needed.

Task analysis describes the steps; chaining determines how to teach them. The illustration shows the routine, not independence levels. In every strategy, help is adjusted and faded according to the child's performance.

The step that saves the most time

Run the routine once before teaching anything — help wherever help is needed, and mark each step independent or not. One run is a useful starting sample, not a stable baseline in the strict sense (that takes several observations), but it is enough to stop you teaching a step the child can already do.

Often the child can already do more than expected, sometimes most of the middle, and the teaching collapses to fewer steps than planned. Skipping that first run is how a program ends up spending weeks prompting a child through things they could already do.

Setting up one chain

Do this
Do the routine yourself and write down each action separately.
One action per line. If a line needs a "properly" or a "correctly", split it.
Do this
Run it once with the child, helping where needed, and mark which steps were already independent.
This first run is a sample of where the child already is, not a formal baseline — but it usually shortens the job.
Do this
Pick a chain: backward if the routine ends in something the child wants.
The last step is the one they do alone, and finishing is its own consequence.
Watch for this
Watch for a step that never fades.
That can mean the step is really two steps hiding inside one line — split it and re-check rather than prompting harder.
Avoid this
Do not teach a chain the child has no reason to finish.
A routine with nothing at the end is the hardest thing to keep going.

What Interlaza does with this

The app carries chaining routines that run one step at a time on their own screen — the step is shown, the adult marks it, and the record keeps which steps are independent. It sits as its own row under Teach a child rather than as a pathway stage: a routine runs step by step on its own screen and stays outside a route’s stage-by-stage progression.

What the app cannot do is write your step list. That comes from watching this child do this routine, and no software has seen either.

Task analysis and chaining: teaching a routine one step at a time