Tic tac toe is one of the first games children play that involves strategy. I remember endlessly playing match after match with friends on scrap paper until there simply wasn't any more room to write.
My friend came up with the great idea of sewing a set herself and then we found this adorable game set by Etsy seller Evgie. The set comes with a little bag to hold all of the pieces. Evgie calls it a travel game but it would fit in at home as well. She's currently sold out but stalk her Etsy shop if you're interested.