Mr Herkabe ranks the students and Malcolm is ranked #1. To differentiate Malcolm from the other kids, he tells him that he is "1 raised to the power of 11". As a teacher, Mr Herkabe should have known that 1 raised to any power is still 1. (He may be perfectly aware of this and just be trying to irritate Malcolm and make the other Krelboynes work harder.)
Mr Herkabe moves Dabney's name card ten places down the rankings (from 5 to 15) and declares:
"Wow! Nine places..."
However, afterwards, he starts moving everyone up by one, putting Dabney at Number 14, so Dabney still fell nine places (5 to 14).