Mature pencil grasps include the dynamic tripod grasp, the lateral tripod, the dynamic quadripod, and lateral quadripod. By ages 6.5 to 7 years 95% of kids have a mature pencil grasp. Modifying a pencil grasp may be needed if fatigue occurs, poor letter formation or writing speed, holding pencil with too much pressure, and tightly closed web space that limits controlled precision of finger and thumb movements.