Set aside what they already know
The most useful thing a parent can do before a session starts is to remove the words that are already settled. A child who is asked a word they have known for years learns nothing from it and notices, every time, that the app is not asking them anything they do not know. Set those words aside in advance and every question that remains is a question worth answering.
This is a small job done once, not a chore repeated daily. Go through the list, and set aside the words your child uses without thinking: the ones they would answer in a blink. Leave the words they half know, and especially the ones they have met and not yet kept. Those are the ones practice is for.
Little and often beats long and occasional
Memory consolidates between sessions, not during them, so five focused minutes a day outperform an hour on Sunday. Pick a slot that already exists — after breakfast, before dinner — and protect it the way you would any other appointment.
End every session while it is still going well, even mid-list. Stopping on a success is what makes a child willing to start tomorrow, and willingness to start tomorrow is the whole game across a year.
Meet words in the wild, not just on lists
A word on a list is recognised; a word met in a story is remembered. When you practise a word, follow it into a sentence: use it at dinner, spot it in a book, notice it on a sign. Each meeting in a new context strengthens the memory more than another look at the same card.
Reading remains the best vocabulary teacher available. A child who reads for pleasure meets more new words in a month than any list contains, and meets each of them doing a job in a sentence — which is how the papers test them.
Make mistakes the plan, not the accident
A wrong answer is the most useful moment in a session: it shows exactly which word is not known yet. Treat it that way out loud. Say what the right answer means, use it in a sentence together, and let the word come back in a few days rather than drilling it on the spot.
Keep a visible record of words that slipped — a sheet on the fridge, a list to print. Watching that list shrink is concrete proof of progress, and proof is what keeps a nine-year-old going through the slow middle months.
Say words aloud
Hearing a word, saying it, and seeing it are three different memories of the same thing, and three memories beat one. Ask your child to pronounce new words and use each in a sentence of their own. A sentence of their own is the test that matters: a child who can use a word knows it, however they scored on options.
If a pronunciation is uncertain, look it up together rather than guessing past it. Mispronounced words are harder to recognise in a listening task and easier to avoid in writing, which quietly shrinks the vocabulary you worked to build.
Keep it kind
Praise the showing up, not the score. Streaks break, hard weeks happen, and a child who believes effort counts will practise through both. Never use a missed word as evidence in an argument, and never compare siblings' scores — comparison teaches children to hide mistakes, and hidden mistakes cannot be revised.
If practice regularly ends badly, change the practice: shorter sessions, easier words, a different time of day. The routine serves the child, never the reverse.