Take three hands-up guesses, not open call-outs. Don't confirm yet — the fun is in whether the rule they sense ("about 3 more each time") holds. What made you say that number? is the question to press on.

First line: point at the gap 4→7→10 and hold out for a pupil to name it as three. The rule is start at 4, add 3. Ask what the fourth mark would be before revealing it.

Second line: the gaps are 2, then 3, then 4 — growing by one each time. The on-screen line names those jumps, but still ask what pupils notice about the gaps first. This is the one that catches people who assume every pattern adds the same amount.

Say the rule in plain words a 10-year-old would use: how much more each time, and where it started.

Talk this one through together — a pupil marks while the class agrees or corrects out loud.

Named order: matchstick squares 4 → 7 → 10 → 13 (rule: start at 4, add 3), then keep adding 3 on the line to reach 16, 19 for step 6 so the class sees the skip-ahead happen; then a shrinking pattern 20 → 16 → 12 (rule: take away 4). Reset the line between the two patterns.

Listen for pupils naming the starting count as well as the jump — a rule needs both. Show the count carrying on past step 4 so nobody thinks they must build every row.

This is the practice round — groups work through the four parts and the class confirms each stage before moving on. Keep it brisk.

Look for:

• Counts recorded as 4, 7, 10, 13 (shared sticks counted once).
• A rule stated with both parts — start at 4, add 3 — not just "add 3".
• Step 6 = 19 and step 10 = 31. Revoice the '3 × step number, plus 1' shortcut (already in the pupil instructions) as a neat way to jump ahead, but let groups reach step 10 by repeated adding if they prefer.

If a group is stuck predicting step 10, point them back at the table: the counts already tell you the jump — keep adding 3 down the column.