It is the question every parent asks first, and the honest answer is that nobody official has given one. Here is what is known, what the criteria actually reward, and a sensible target to work towards.

There is no official word count

The NSW Department of Education does not publish a word limit or a recommended length for the Selective writing task. The marking criteria do not mention length at all. Set A rewards content that is "chosen" and "developed", form that fits the task, and a controlled style. Set B rewards sentence variety, punctuation and spelling. A piece can hit every one of those descriptors at 280 words and miss all of them at 600.

Tutors commonly suggest 300 to 400 words. That is a reasonable guide, and the rest of this article explains why it comes out there, but treat it as a consequence of good practice rather than a rule.

The 30 minutes do the maths for you

Students have 30 minutes including planning. A sensible split is about 5 minutes to read the prompt and plan, 3 minutes to check, and roughly 22 minutes of actual writing.

How many words fit in 22 minutes depends on composing speed, which is much slower than copy-typing speed because the student is thinking as they type:

  • At 14 words a minute while composing, 22 minutes gives about 300 words.
  • At 20 words a minute, about 440 words.
  • At 8 words a minute, which is common for a Year 5 who types with two fingers, about 175 words, and that is where length really does become a problem.

So length is mostly a typing question. If your child's pieces are short, the fix is usually typing speed and a quicker plan, not "write more".

Too short: when length genuinely costs marks

Under about 200 words it is hard to show the things Set A asks for. A narrative needs room for a problem to develop and resolve; a persuasive piece needs three reasons with an example each plus an answer to the other side. Very short pieces tend to land in Band 3 or 4 not because they are short but because the ideas never get developed, which is what the descriptors measure.

The problem

The piece stops at 150 words with the story barely started, or the persuasive letter gives one reason and a conclusion.

The fix

Build composing speed with daily short typing practice, and plan three beats before writing so there is always a next thing to say.

Too long: the more common mistake

Students who write fast often run into the opposite problem. Five hundred words with no time to check means the Set B slips stay in. Six hundred words means the ending is rushed or missing, and the examiners' own comments on a real Band 6 sample show they marked it down for an unsatisfying ending.

The problem

A brilliant middle, no ending, three homophone errors nobody had time to catch.

The fix

Decide the ending before you start, and stop writing new material at the 25-minute mark whatever is on the page. A planned final paragraph is worth more than another paragraph of middle.

Realistic ranges by text type

These are not rules, just where well-made pieces by Year 6 students tend to land in 30 minutes:

  • Narrative: 300–450 words. Stories need the most room, but one setting and a few hours of story time is plenty.
  • Persuasive: 250–400 words. A position, three reasons with examples, a response to the other side, a call to action.
  • Discursive: 300–400 words. Two sides need fair treatment, then a conclusion.
  • Descriptive: 250–350 words. Density matters more than length; five precise senses beat ten vague ones.
  • Informative, including reports: 250–350 words. A headline, a lead paragraph covering who, what, when and where, details, quotes, what happens next.

See text types explained for the structure of each.

What to do with this

  1. Measure, don't guess. Have your child write one full piece on the practice tool. The word count and words per minute appear when they finish, so you know their natural length today.
  2. Set a target from the maths, not from a forum. If they compose at 12 words a minute, 260 words is a good piece for now and 400 is not a realistic goal this month.
  3. Work on the cause. Short pieces: typing and planning. Long unfinished pieces: planning the ending and stopping on time.
  4. Judge by the bands, not the count. Read the Set A comments on a marked piece. If they say "general" or "undeveloped", the fix is more specific detail, which usually adds words anyway. If they say "unfinished" or "rushed", the fix is fewer.
Goal

A complete piece with a beginning, a developed middle and a planned ending, checked, in 30 minutes. Whatever number of words that turns out to be is the right number.