Attention and Concentration

A 2-year old should concentrate for 7 min.
A 3-year old should recognise people and remember names; remember where stuff is put away ; should be able to amuse himself for 30 min and should be able to concentrate on one game for 5-10min.
A 4-year old should be able to amuse him for 60 min and should be able to concentrate on one game for 10-15min.
A 5-year old should be able to concentrate at a table for 20min; recall 5 numbers on memory recall and recall 5 objects.
A 6-year old should be able to concentrate at a table for 25min; recall 6 numbers on memory recall and recall 6 objects.