The decision to transition from large-motor writing to pencil and paper should be based upon the individual student's development. Many students will find great success by learning to write a letter using large-motor skill, then immediately writing the letter with a pencil. Other students with less developed fine-motor skills benefit from extended large-motor practice.
To assess readiness, periodically provide the child with a pencil. Demonstrate how to hold the pencil and position the paper. Ask the student to write two to three phonograms that she can already form easily with large-motor writing. If the student is able to hold the pencil and form recognizable letters without frustration, she is ready to begin practice with pencil and paper. If the student is deeply frustrated or the letters are not recognizable, continue large-motor writing for now, while providing fine-motor activities that are not related to handwriting.