Around 3 years old

Better coordination for walking, running, jumping, climbing and swinging;

Walking up stairs alternating feet;

Mastering of toilet training with few accidents;

Unbuttoning buttons

Learning and using many new words;

Understanding numbers;

Naming colors and body parts;

Pointing to details in pictures when asked about;

Using three-word sentences

Experiencing emotions with intensity;

Identifying own and other's feelings and thinking using words;

Showing concern by offering comfort;

Struggling to regulate emotions when tired, stressed, or with routine changes;

Some difficulty separating from caregivers

Engaging in imaginary play;

Beginning to see peers as friends;

Avoiding sharing;

Pushing, hitting, yelling, and crying during playtime;

Imitation of others' behaviors;

Becoming a little aggressive and defiant.

Around 4 years old

Throwing and catching a ball;

Stringing beads, stacking blocks and using scissors;

Balancing on one foot;

Expanding vocabulary;

Asking a lot of questions;

Talking in complete sentences;

Following three-step instructions;

Reacting strongly, with intense feelings;

Loving and hating many things;

Growing sense of humor;

Throwing of some temper tantrums;

Often fearful and anxious; 

Fearing monsters and other imaginary creatures;

Having a preferred friend;

Engaging in group play;

Enjoying talking but not listening;

Increasing awareness of differences between self and others; 

Increasing interests in differences between boys and girls;

Around 5 years old

Getting dressed independently;

Coloring inside the lines and writing letters;

No longer tiptoeing, riding a bicycle, and skipping;

Pencil grasp;

Jumping backward

Mastering simple planning and organization;

Ascribing life and movement to inanimate objects (e.g., stuffed animals);

Reciting phone number;

Telling stories with beginning, middle, end;

Understanding past and future;

Feeling secure with guidelines and routine;

Expressing feelings verbally;

Demonstrating self-control and less impulsivity;

Becoming more independent;

Gaining sense of competence

Experiencing fluctuations in emotions

Saying "sorry" after making a mistake

Having a group of friends;

Cooperating and following rules;

Seeking of adult approval;

Engaging other children in play and conversation;

Sometimes, opposing 

Around 6 years old

Dressing, bathing, and tying own shoes;

Riding a bicycle without training wheels;

Writing short sentences

Expanding vocabulary and verbal communication;

Asking what words mean; 

Following complicated directions;

Understanding seasons and holidays

Knowing the days of the week;

Reading stories out loud;

Sensitive to criticism and correction;

Emotionally volatile under stress;

More aware of others' needs and feelings;

Playing board games;

Cheating to win games;

Having a best friend;

Enjoying going to school;

Lying to avoid punishment;

Pleasing teachers;

Expressing fears of caregivers dying;