Observing certain attitudes/behaviors may signal that a change is needed and may be overdue.
1) http://giftedissues.davidsongifted...._many_kids_in_GT_program.html#Post174817
2) http://giftedissues.davidsongifted....acts_of_being_3_years_ac.html#Post230029
3) http://giftedissues.davidsongifted....de_skip_vs_gifted_progra.html#Post241385

The hair-pulling may now be a child's imperfect coping mechanism, attempting to deal with the deep stress of feeling trapped and helpless as his hopes, brain cells, and natural curiosity die off at the hands of the school system which does not meet his academic needs. Can the child be provided with some semblance of control/influence over his learning environment, with academic challenge and support based on his ability and readiness? Unfortunately, if the maladaptive behavior is not quickly replaced with a different form of fidgeting which does not result in self-harm, it may become an ingrained pattern (diagnosed as trichotillomania, a mental disorder).

Meanwhile, it is great that the child receives challenge/support/enrichment outside of the classroom. Although it falls far short of the challenge/support the child should be receiving throughout the school day, it shows the child that you understand and care about his academic needs, and that he can talk to you about his unsatisfying/boring school day experiences.