Lay the paper bag flat and use a marker and a ruler to draw lines across the bag to create the bricks. Draw the vertical lines to create each brick. Color the bricks with a red crayon.
Cut the hearth from black construction paper and glue to the bag.
Cut flame shapes from red construction paper. Use that as a guide to cut flames from yellow and orange as well, then trim down the orange so they are smaller than the red. Trim down the yellow so they are smaller than the orange. Glue the flames (red, orange, yellow) to the hearth.
Fill bag with crumpled paper to give it some body and close the top.