Crossing Midline: The Developmental Milestone Every Parent Should Know About!

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In childhood development, there is a fundamental milestone that is often overlooked but holds profound significance – crossing midline. This seemingly simple action involves reaching, touching, or moving across the imaginary line that divides the body into left and right halves. From infancy to adulthood, the ability to cross midline plays a pivotal role in physical development. Let's look a little deeper into this fascinating phenomenon and explore its importance.

The Basics of Crossing Midline

To understand the significance of crossing midline, it's essential to grasp its mechanics. The human brain is divided into two hemispheres – left and right – each responsible for controlling the opposite side of the body. Crossing midline involves coordinating movements that require one hand, foot, or eye to move into the space of the opposite side of the body. For example, when a person reaches across their body to scratch an itch on the opposite arm or crosses one leg over the other while sitting, they are engaging in crossing midline activities.

Why is crossing midline important in early development?

During infancy and early childhood, crossing midline serves as a foundational skill that lays the groundwork for various aspects of development. Babies instinctively begin to explore crossing midline as they reach for objects, grasp toys, and eventually learn to crawl. These early movements help to strengthen neural connections between the brain's hemispheres, fostering communication and coordination between the two sides.
Crossing midline activities are closely linked to the development of hand-eye coordination, spatial awareness, and fine motor skills. As children engage in tasks like drawing shapes, threading beads, or completing puzzles that require crossing midline, they are honing essential abilities that will serve them in academic and daily life tasks.

How can I tell if my child is having difficulty crossing midline?

When a child avoids crossing midline, they often show a preference for using both hands equally in activities such as handwriting, coloring, and cutting with scissors. They may resort to awkward movements, such as shifting their body position, to avoid crossing midline. Here are a few things to look for that may suggest your child is having trouble crossing midline:
  • Weak pencil skills
  • Frequently loses their place while writing or reading.
  • Switches hands midway through tasks like drawing, coloring, painting, or writing.
  • Consistently uses the left hand for tasks on the left side and the right hand for tasks on the right side.
  • Struggles with activities requiring coordination.
  • Difficulty distinguishing between the right and left sides of the body.
  • Rotates their body to pick up objects instead of reaching across their body.
  • Unable to draw "X" or "+" shapes.

How can an occupational therapist help?

Occupational therapists can help children with difficulty crossing midline by designing activities that encourage the use of both hands together, such as playing catch or using tools like scissors. They also teach specific exercises and activities that involve crossing midline, such as drawing shapes that require crossing over from one side of the body to the other. By using these strategies, occupational therapists can help children improve their ability to cross midline, leading to better coordination and motor skills. Like every other form of therapy, the earlier you start OT, the more effective it will be.

What can I do to help my child cross midline?

Here are 5 activities that you can try at home to promote midline crossing:
BALL PASS: Sit back-to-back with your child, each holding a ball or toy. Pass the object to your child on one side of your body, both of you rotating your trunk and using both hands to hold the object. Then, rotate to the other side for your child to pass the ball back to you. Repeat this process ten times on each side.
FIGURE EIGHT: Drawing figure eights as a race car track is a creative and engaging way to help improve midline crossing. To do this activity, provide your child with a large piece of paper and some markers or crayons. Encourage them to draw a figure eight shape, which naturally involves crossing midline as they move their hand from one side to the other and back again. You can make this activity even more interactive by turning it into a "race." Have your child draw two or more figure eight tracks on the paper and then use toy cars to "race" around the tracks, crossing the midline as they move the cars from one loop to the other.  Modify the activity by having them trace a figure eight with their finger in shaving cream or while in the bathtub. This tactile approach adds a sensory element to the task, making it engaging and stimulating while still providing practice in crossing the midline.
DRAW RAINBOWS: DrawingDrawing rainbows can be a great activity to help your child practice crossing midline. To do this, have your child sit at a table with a piece of paper and some crayons or markers. Start by drawing a large arc on the paper, starting from one side and curving over to the other side. Then, ask your child to continue the arc, crossing over the midline to complete the rainbow shape.
CROSS CRAWL EXERCISES: Stand or sit comfortably and touch your right elbow to your left knee, then your left elbow to your right knee, crossing the midline with each movement. This can be done slowly or quickly to increase the challenge.
SORT OBJECTS:  Engage in sorting games by placing objects to sort on the left side and containers or spaces on the right side. Sort items like coins, blocks, marbles, etc., by color, shape, or size.


Crossing midline is a crucial skill that impacts various aspects of a child's development, including coordination and motor skills. By incorporating fun and engaging activities that promote midline crossing into everyday routines, parents can support children in developing this essential skill. Ultimately, fostering midline crossing helps children become more proficient in daily tasks and sets a strong foundation for their overall development. If you have concerns about your child’s ability to cross midline give us a call for a free 15-minute consultation with one of our occupational therapists.