Birth - 6 mos. = limited manipulative exploration, can create and maintain interesting events.

6 - 12 mos. = greater manipulative exploration; by 9 mos., choose novel objects and explore these longer with more manipulation of the details of the object; by 12 mos., mechanical interaction with objects (push buttons, pull levers, etc.)

12 - 36 mos. = change actions on object to conform to cultural meanings, can explore interrelationships between 2 objects or events, begin to control and regulate play environment; at 12 mos., object substitutions begin by using real objects as they are intended; at 18 mos., use similar objects are substitutions (i.e., salient affordances)

3 yrs. = sensory and motor play is combined so child can construct with blocks and clay, play with water and sand, ride vehicles, climb structures; very divergent object substitutions, create imaginary objects to facilitate pretense

4 - 5yrs. = emergence of imaginary playmates

Pretend play functions to aid understanding of physical and social world:

1 yr. = simulate typical, daily routines and is directed toward the self

16 - 18 mos. = directed toward animate or inanimate others, use of counterfactuals (i.e., mappings)

24 mos. = participants (even dolls) are agents in pretense and are not merely directed

3 yrs. = children can be narrators of a script in pretense

Sociodramatic play with peers during preschool is characterized by turn taking, reciprocal interaction, assumption of roles, metacommunication about on-going scenario.

First 2 yrs. = play acts are not integrated

18 - 24 mos. = can link two acts in play

by 2.5 yrs. = creating more complex action combinations

These last two trends parallels language development and the linkage of two or more words in utterances.