Staff reported resident was in the dayroom sitting next to staff when the lead technician came on the unit and confirmed this resident was on unit restrictions due to safety and previous behaviors. Resident got upset and start vigorously scratching her arms causing irritation. While staff was trying to redirect, resident got up and walked to the end of the hallway and staff saw that she had a crayon. Staff confiscated crayon and processed with resident and was able to de-escalate. Resident would not report where she got the crayon. Resident to continue self-harm precautions.