This game uses three spelling variations of the 'er' sound, so it will suit learners at this stage of ability. I use it in Intervention, but you can also add it to a Literacy Centre after your intervention group has learned to play. That way they can teach the rest of the class. It's a great way to be inclusive.
You will see the Tic Tac Toe format from the Preview and I have two sets of sentence cards (36 sentences to a set). The player reads the card and places it according to the spelling. There is an answer sheet for this purpose which makes it an independent activity.
I have a Bossy R Bundle which includes this game and more as well as five Posters.