OuiSi · Math

Grid references

Beta

Grades 2–3 Teaching 30 min Plus 4 to set out, 3 to clear Class groups of 4–6 Set any Prep 16 cards per group, 25 for grade 3, sticky labels

set out 4′ Build and label 7′ Find the square 10′ Describe and locate 10′ Close 3′ clear 3′

Goal: Children read a square's reference, then produce one — the harder half — using the same notation as the index of an atlas.
Materials: One OuiSi Photo-Card set. Sixteen cards per group in a four-by-four square, or twenty-five in a five-by-five for grade 3. Sticky notes or scrap paper for labels.

Grade 2: Four by four. You call the references, children point — the full 30 min
Grade 3: Five by five, and children call the references themselves in step three — the full 30 min

1 · Build and label

7 min

Each group lays sixteen cards in a square, four across and four down. Grade 3 lays twenty-five, five by five. Tidy rows matter here.

Put letters along the top — A, B, C, D. Put numbers down the side — 1, 2, 3, 4.

Grade 3 runs to E and 5. Everything else in the lesson is identical.

Let them place the labels themselves. Working out which way a column runs is the first real moment of the lesson, and a group that gets it wrong will fix it in step two.

2 · Find the square

10 min

You call positions. Everyone points at once — no hands up and no turns.

Finger on C3. Now B4. Now A1.

Once pointing is quick and confident, turn it around.

I can see a card with something blue in it. Tell me where it is.

Reading a reference is easy. Producing one is the skill, and this is where you find out who actually has it.

3 · Describe and locate

10 min

One child in each group turns away from the grid. The rest silently pick a card.

Describe your card to them. No pointing, and do not say where it is.

When you think you know which card it is, say its reference out loud.

Rotate who turns away every two rounds.

Two skills at once, and when the reference is wrong it is usually a vague description rather than bad grid work. Worth saying that to the group.

4 · Close

3 min

Give me the reference for the card you would most like to keep.

Watch for

Letter and number swapped. Constant at this age. Point at the labels rather than correcting the child — the grid answers the question itself.
Crooked grids. A square that drifts out of line creates genuine ambiguity. Straighten it before step two, not during.
Pointing instead of describing in step three. Hands under the table if it keeps happening.
Groups larger than six. Too many children around one grid and the quiet ones never call a reference.

Adapt

Grade 2 — stay at four by four and keep calling the references yourself throughout.
Grade 3 — five by five, and let groups run step two for each other.
Map skills tie-in — the same notation as an atlas index. Bring a map out straight afterward and the transfer is immediate.
Multilingual learners — letters and numbers carry step two with no English at all.
Motor or vision needs — space the cards further apart, and a partner may point on request.
Finished early — one child moves two cards while the group looks away, and the group finds which references changed.

Curriculum links. Constructing and labeling a grid · Reading a reference to locate a square · Producing a reference for a chosen square · Describing an object precisely without pointing · Transferring the notation to an atlas index.
Standard codes vary by state and district — these are the skills exercised, for you to map to your own.

For grades 4–5 see Ordered pairs, which replaces the letters with numbers and raises the question of which one you read first.
From OuiSi Capture. The grid is borrowed from the Capture play, without the clue-giving.