Supplies you need:
2-4 paper towel rolls (or wallpaper roll)
2 yogurt cans
Paint and paintbrushes (optional)
Take a box and cut it around 20 inch to 7 inch (50 cm to 18 cm)
Take 2 paper towel rolls ( i took wallpaper rolls) and place these on the cardboard as shown on the picture and hot glue it.
Take a knife and make half a circle (based on the size of your marble) and then cut paper towel roll in half as shown on the picture and then hot glue it
Cut the 2 yougurt cans as shown on the picture
Hot glue them as shown in the picture
Hot glue popsicles so the exit line is fit for your marble size.
Try your game - it should work like in my video or even better))))))))