harry potter - Who is the head of Ravenclaw?

We're pretty familiar with the heads of the other houses:

• The Head of Gryffindor is McGonagall


• The Head of Hufflepuff is Sprout


• The Head of Slytherin is Slytherincess Snape, then Slughorn

But who is the head of Ravenclaw?

Answer

Filius Flitwick is the head of Ravenclaw.

Hogwarts Charms professor and Head of Ravenclaw house

Pottermore - Character Profile - Filius Flitwick

Interestingly Filius and Minerva both had a similar experience with the sorting hat which featured opposite outcomes, Minerva into Gryffindor and Filius into Ravenclaw.

After five and a half minutes, the Sorting Hat, which had been vacillating between the houses of Ravenclaw and Gryffindor, placed Minerva in the latter. (In later years, this circumstance was a subject of gentle humour between Minerva and her colleague Filius Flitwick, over whom the Sorting Hat suffered the same confusion, but reached the opposite conclusion. The two Heads of house were amused to think that they might, but for those crucial moments in their youths, have exchanged positions

Pottermore - Writing by JK - Professor McGonagall