Infants (0-12 months):

• Holds head up when lying on stomach (2 months)
• Pushes up onto elbows/forearms when on stomach (4 months)
• Rolls from stomach to back and vice versa (6 months)
• Pushes up with straight arms when on stomach (6 months)
• Leans on hands to support themself when sitting (6 months)
• Gets to a sitting position by themselves (9 months)
• Sits without support (9 months)
• Pulls up to stand (12 months)
• Walks, holding onto furniture (12 months)

Toddlers (1-3 years):

• Takes a few steps on his own (15 months)
• Walks independently (18 months)
• Climbs on and off a couch or chair without help (18 months) 
• Throws and kicks a ball (24 months) 
• Runs (24 months)
• Walks up a few stairs with assistance (24 months) 
• Jumps off the ground with both feet (30 months) 

Preschoolers (3-5 years):

• Pedals a tricycle (3 years)
• Walks up a few stairs independently (3 years)
• Catches a large ball (4 years)
• Stands on one foot for a short time (4 years)
• Skips with alternating feet (5 years)
• Hops on 1 foot (5 years)

School-age (6-12 years):

• Jumps rope (6-7 years)
• Rides a bicycle independently (7-8 years)
• Throws and catches a ball with precision (8-9 years)
• Skates, rollerblades, or skateboards (8-10 years)
• Performs more complex gross motor skills, such as running, jumping, and skipping with ease and coordination