A student can understand the material completely and still not get the work done.
That gap is usually executive function — the set of skills that handle starting, sequencing, holding a plan in mind, and finishing. It's not effort and it's not attitude, and treating it as either makes everything worse.
What follows is practical structure. It isn't a substitute for a diagnosis, and if this describes your household, a family doctor or psychologist is where that conversation belongs.
For a lot of students the work isn't difficult once they're in it. Getting in is what doesn't happen.
Make the first step absurdly small. Not "do the chemistry assignment" — open the book to page 214 and copy out question 1. The threshold has to be low enough to clear without deciding anything.
Decide it the night before. Choosing what to work on is itself a task, and it's the one most likely to fail. If tonight's first move was decided yesterday, tonight only has to execute.
Same time, same place. A trigger the environment supplies means less has to come from the student.
An open-ended instruction — do your homework, study for the test — is where things stall. There's no defined start and no visible end, so there's nothing to begin.
Breaking each question into recognize, first move, work it out, verify does something specific for this: at any moment there's exactly one small thing to do, and each piece finishes. That's four completions per question instead of one large undefined task, and completion is the thing that makes the next step possible.
It also removes the working-memory load of holding the whole problem in your head at once. You only have to hold the current step.
Short blocks with real ends. Twenty or twenty-five minutes, then stop. Long sessions are theoretically more efficient and practically don't happen.
One surface for everything due. If tracking lives in memory it will fail, and that failure gets read as not caring.
External reminders that aren't a person. When a parent is the reminder system it becomes a relationship conflict on top of a scheduling one.
Write things down at the moment of hearing them. The instruction that was mentioned once in class is gone by the bus.
And immediate feedback where possible. Finding out a week later whether you did it right is hard for anyone to learn from and harder here.
Stop treating inconsistency as a character problem. A student who does brilliant work on Tuesday and nothing on Wednesday is not choosing that.
Stop adding more supervision as the response to a missed deadline. It rarely helps and it costs the relationship.
And stop comparing to a sibling or a classmate who "just gets on with it." Different wiring, and the comparison lands as evidence of being defective, which is its own drag on getting started.
Small steps, one at a time, with the week already laid out — the structure is the product.
Related: Your kid can't see their own week · When the workload is the problem