GRADE 1 · ALBERTAOUTCOME AB-G1-1P1
L3 · The missing element
Learning goal
“I can find the part that is missing in a pattern.”
Missing — not there; a part that should be in the pattern is gone.
Gap — the empty spot where the missing part belongs.
Belongs — fits in a place; the gap has one part that belongs in it.
Worked example
Pattern: red, blue, red, ___, red, blue. Step 1: Find the core: red, blue. Step 2: Walk the core and count the places: red(1), blue(2) - red(1), gap(2) - red(1), blue(2). Step 3: The gap is at place 2 of the core. Place 2 is blue. Say it: the missing part is blue. Say it plainly: the gap has a place in the core. Find the place, and the core tells the part.
Check yourself — explain it
How do you find a missing part?
Paired problem — example still visible
Pattern: dog, cat, dog, cat, ___, cat. What is missing? -> Dog (places: dog(1), cat(2) - the gap is place 1)
Faded completion — last step is yours
"Pattern: A, B, B, A, ___, B. The core is A, B, B. The gap is at place 2. The missing part is ___." -> B
Ready to practise?
8 scored questions with a 3-rung hint ladder. Mastery needs 7/8 plus both gate questions.