Related:What is a fair Scrabble handicap
Scrabble is a great game for competitive type A types and the learning curve is STEEP at first. Great game. Like most games, house rules vary and are fine as long as everyone agrees.
I enjoy introducing new people to the game, but it's not fun for anyone if I win the first game by 250 points. One thing I find helpful is giving everybody a list of 2 letter words. It's just not fair otherwise because of course I have them memorized, yet a newbie isn't going to know that QI and ZA are legal plays.
Assume relatively equal mastery of the English language. What else can be done to help those first few games be competitive?