Cognitive Development

By 9 months, most children:

• Respond to familiar people and objects in a way that is different from the way they respond to unfamiliar people or objects
• After repeated experiences with the same objects and persons, sometimes remember that unseen objects are still there (e.g., remembering that a ball is under the blanket)
• Attend to unexpected events

By 18 months, most children:

• Point to, or in some other way indicate, familiar people and objects when they are named
• Remember the location of objects that are meaningful to them
• Demonstrate an understanding of object permanence, such as reaching under a blanket to retrieve a stuffed animal

By 24 months, most children:

• Demonstrate a solid understanding of object permanence (e.g., looking for a car after it enters a tunnel, finding play dough that has been put away in a cupboard)
• Purposefully put two actions together in sequence (e.g., grabbing a large ball and rolling it)

By 36 months, most children:

• Remember and communicate what happened earlier in the day; recall basic components of recent events (e.g., are able to follow a daily routine)
• Know where things are kept in familiar environments and can retrieve them when needed
• Successfully follow two-step directions

By 48 months, most children:

• Communicate with some detail about events that happened in the past
• With support, retell or reenact familiar stories, including such details as characters, phrases, and events
• Put several objects or groups in order by a quantitative attributes (number, length, etc.)
• Solve simple word problems with totals of five or fewer items (e.g., concluding that they have a total of four pencils if they already have three and are given one more)
• Successfully follow three-step directions

By 60 months, most children:

• Accurately recount past experiences in the correct order and include relevant details
• Retell a familiar story in the proper sequence, including such details as characters, phrases, and events
• Remember more and more minute details from a story and are able to answer questions accurately (e.g., “How did the peddler feel when the monkeys didn’t give him back his caps?”)
• Place four or more objects or groups in order of a quantitative attribute (number, length, etc.)
• Solve simple word problems with totals of 10 or fewer items (e. g., concluding that they have nine grapes if they have seven and are given two more)
• Successfully follow detailed, multi-step directions