Some letter combinations work exceptionally well, for instance, the word: Quiz
What makes this word so unique and high scoring, despite it being only 4 letters, is the fact that it uses the 2 highest scoring letters: Q and Z. Because Q and Z are worth 10 each, and U and I combined are 2, you immediately have 22 points.
A key to doing well, is using as many Q's and Z's as possible, in the one word.
The two highest scoring words in Online-Scrabble, not suprisingly, contain the letters Q and Z.. one more than one occasion.
Quizzically - One Q, Two Z's. Straight away you have thirty. Because of various other high scoring letters such as C and Y, the word comes to a total of 43 points. If you are lucky, and get a Double Word score, or a Triple Word Score, this 43 letter word could turn into 86 points, or even 129 points.
Quizzicality - Like quizzically, many high scoring letters are the key. Because of the extra letter, you are looking at an extra point. And if you are lucky enough to get a Double Word Score or Triple Word Score, you would get 88 points and 132 points respectively.
Use the chart below to find the best combinations using the key letters: Q and Z, and when you can: X and J.