What is "crossing the midline" all about? - LeafSpring School

April 25, 2019

What is “crossing the midline” all about?

Crossing the midline refers to the imaginary line, from head to toe, which divides the body into left and right sides. It is the spontaneous act of our arms, legs, and feet crossing from one side of the body to the other. Crossing the midline is a learned trait and does not typically begin developing until 8 months and by age 4 it can typically be done with ease.  Prior to having this skill, children will pick up an object with one hand and pass it to the other when reaching the center “or midline” of the body.

But why does it matter? Both the left and right side of the brain are designed to carry out specific tasks.  When we cross the midline, we force both sides of the brain to work together, which helps develop higher order thinking skills, sensory integration, body awareness, and critical thinking skills, etc. Children who can cross the midline often find it easier to retain information and stay focused, a vital part of being “kindergarten ready.”

Crossing the midline - left and right brain functions


Some signs a child may be struggling with crossing the midline may be:

  • A child swaps objects from hand-to-hand at the midline point
  • Delayed crawling, jumping, skipping (shows lack of coordination between both sides of the body)
  • Poor fine motor skills (pencil grip, handwriting)
  • Trouble tracking words from left to right
  • Uses right hand activities on the right side of the body and uses left leg activities on the left leg of the body.


So, what can be done to help support midline development? Simple games and activities can be incorporated in daily routines. Simon Says, Twister, and marching games are great ways to encourage children to reach across their bodies while having fun. Children can pop bubbles, bang objects together at the midline, or play passing games which require children to reach from one side to the other.  One NAEYC article encourages breakdancing as a way get both arms and legs to cross the midline. Children will love getting energy out while they build a working partnership between both sides of their brain.

More information on crossing the midline: