I love using Bananagrams with my memory care community. Here is the Bananagram game I use. But these giant scrabble tiles would also work well for these games although they are quite pricey. You could also try making your own by using stencils on a card stock or cardboard.
Where is the Letter?
In this game, you spread out all the tiles on the table and just ask the residents to find each letter by one by one. Some letters will have more than just one, see if they can find them all.
Alphabetize Order
In this game, ask the residents to find each letter one by one in order and then line them all up.
Spelling Words
In this game, say an easy word to spell and ask residents to find each letter of the word one by one.
Words Starting With
In this game, select one letter and see how many words the group can come up with starting with that one letter.
Simple Scrabble
In this game, give all residents at least 7 letters and place down one word on the table. Have residents go one by one and see if they can add more word to the table from the connecting word. The more letters each person starts with the easier it will be for them.