||4 – 5 years approx.
In the SECOND PERIOD repeatedly ask the child to show you the various amounts 10, 20, 30. Do this in sequence initially and eventually out of sequence.
In the THIRD PERIOD, isolate each amount and ask the child (in order) “what number is this?”
Consolidate by asking the child again to tell you the name of all three numbers.
The next time you work with this, do one known and two unknown numbers.
End the work cycle.