# Open a ten, keep the amount

Make two packing plans for the same thirty-two marks. Choose safe pieces, marks, tactile objects or tell an adult where to move them.

1. Show the whole and each part.
2. Try another split using the same objects.
3. Check what stayed the same. Keep a useful plan or change it.

Choose a job: [Drawing labels](../choices/day-45-route-1.md), [Game-card plan](../choices/day-45-route-2.md), [Display dots](../choices/day-45-route-3.md). Use a smaller amount when useful. An empty part is zero.

[My paper organiser](../PAPER.md) · [Part Builder](../workspace/index.html) · [Models and empty spaces](../AIDS.md).

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[Full teacher plan](../teacher/day-45.md). If both versions remain, mark the ten represented objects and remove their old strip as the singles replace it. If the whole changes, count a new smaller account before/after one exchange. Use local safe materials and usual communication/access supports. Child-directed adult physical work and child mathematical choice stay distinct. Preserve first thinking before feedback; a drawing is not an actual outside inventory or performance event.

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