As an introduction to the -at word family, I begin with the book, "The Cat in the Hat." I go through the normal prediction, read, discuss process with the children.
After finishing the story we play with -at rhymes, eg. there was a cat in the story, what rhymes with cat? etc.
I take out the large hat and the index cards(prepare index cards with simple words that are part of the -at family and are not part of this family) and we go through the index cards, only placing -at words in the hat. When we've gone through the cards, we pull the rhyming -at words out of the hat and listen to them again.
On the second day, we pull out the hat and listen and read the words again. Volunteers then tape the cards to the board or wall. Look at the words and talk about the similar endings of the words and how only the first sound changes.
Pass out the black construction paper. Show the children how to fold and cut out a black top hat form. Instruct them to then spread out on the floor and practice writing their own list of -at words, emphasizing the repetitive nature of the words. Hang the finished hats for the children to use in their classroom writing.