My dad used to 'twiddle' his thumbs...interlock your fingers in front of you,and rotate your thumbs around each other...you'll get the hang of it...he said to rotate one in one direction,and the other in the opposite,I still say its impossible.
Im ADHD. This is a question made for me to answer. If u are in class break off the little clip of a machanical pencil and slowly try to break it into peices. If u don't mind being risky, wad up little peices of paper and try to flick them into the trash can.