Coloured pencil
Coloured pencils were pencils which came in many colours, including blue, green and red. Children would often draw with coloured pencils, mess up, and then scribble on the drawing to cover up their mistake. (TV: Fear Her)
Graphon Narmolis, a shape-changing criminal, once assumed the identity of a coloured pencil, and was used by Janie, a schoolgirl, to write her homework. (COMIC: Pencil Pusher)
When, in 2012 London, the Isolus took over Chloe Webber, a lonely child, Chloe began drawing people and objects — snatching them from space-time, and sucking them into her paper. She did this under the influence of the Isolus, who was lonely as well, trapped away from her family over around four billion. Not only could Chloe suck living organisms into drawings, but she could also create organisms from drawings, as she did with the scribble creature, a creature made entirely from graphite, and her father. The Isolus, with Chloe unconscious, showed a skill of pencil drawing quite capably and quite quickly. Trish Webber, her mother, would hide her pencils, but she kept a secret stash in a doll. The Isolus was eventually freed when the Tenth Doctor and Rose Tyler found its spaceship, and Chloe was no longer capable of extracting life through drawing. (TV: Fear Her)