How many words start with KL?

10, from 5 letters up to 5. All of them are on this page.

What is the highest scoring word that start with KL?

KLUTZ at 18 points in Scrabble, and KLUTZ at 20 in Words With Friends, because the two games score the tiles differently.

KLANG, KLAPS, KLETT, KLICK, KLIEG, KLIKS, KLONG, KLOOF, KLUGE, KLUTZ.

10 of them: KLANG, KLAPS, KLETT, KLICK, KLIEG, KLIKS, KLONG, KLOOF, KLUGE, KLUTZ.

There are 10 of them. The highest scoring is KLUTZ at 18 points in Scrabble, and the set averages 11.8.

Most common words first, then the rest A to Z.

All of them: Word lists.