I made one marble racer with the pool noodles, but I wanted one like the large wood ones, that had the marble race down one inclined plane after another. No wood and the tools are not set up in the new wood shop yet. I scavenged a nice sized cardboard box, which sat in the back seat of my car for about 2 weeks while I thought about it. Finally, I had the time to create what I had spent quite a bit of time thinking about. So this is how I made a cardboard marble racer.

Step 1:

Supplies:
1 large cardboard box (mine was 19”x15”x14” (48cm x 38 cm x 35cm))
Spray paint (you choice of colors- I used leftovers from other projects)
20 1½ inch (4cm) brad fasteners (office supply store +/-$3)
Yard stick
Pencil
Craft knife (+/- $3 depending upon what you buy and where)
Marker
1½ inch (4cm) masking tape (stuff I had)
Awl (one I have had for years)
Masking tape (not shown)
(I showed glue but I didn't use it)

Step 2:

Measure 3 inches (7.5 cm) from the bottom of the box and leave a mark with your pencil. Do this several times on all 4 sides of the box. Connect the dots so that they are a straight line all the way around the box.

Step 3:

Use the craft knife to cut the bottom of the box

Step 4:

away from the rest of the box.

Step 5:

Cut on off the long sides of the box away from the rest of the box and put the left overs aside (for another project maybe). On this long piece measure 4 inch (10cm) strips

Step 6:

and cut out 4 of them, using your box knife.

Step 7:

On one of the long strips, measure and draw a line ½ inch (1.25 cm) long on the left long side and draw and measure a line 1 inch (2.5cm) wide on the right side.

Step 8:

Take the craft knife and cut half way through the cardboard long the drawn line. This is now a seam, so bend the cut line with the crack in the cardboard on the outer edge.

Step 9:

Repeat with the other three strips.

Step 10:

Now take the masking tape and tape the shorter (½ inch-1.25cm) side of the long strips so that the seam creates a 90° angle. This is the wall that will keep the marble from sliding over the edge. The other wall is what will be the one that will be attached to the back of the box. These pieces are now marble ramps.

Step 11:

Now spray paint the box bottom and the 4 strips, whatever colors you want. Make the two parts different colors. The main box was painted yellow and the strips, blue.

Step 12:

Next create the end flaps to attach the start of each ramp to the side wall. Again cut it part of the way through, and removed the excess corners. Have the high wall all on the same side and 2 of the ramps with the end flap on the right side and 2 with the end flap on the left side. You may discover that you will need to cut off a ½ inch or so from the other end of each ramp so that there is enough room for the marble to drop off the end of a ramp on to the ramp below.

Step 13:

Turn the box bottom side up. You want to get an idea of where the slanted lines for the ramps to go along. I measured 1 inch (2.5 cm) down from the top and 6 inches (15cm) down from that, and repeated the process until I had marks for starts and end with slants on the two ends. Next draw the lines that created the slants for 4 ramps. I didn’t end up following these lines exactly, but close enough.

Step 14:

On the back side of the high wall of the ramp, mark dots toward the center, every 3 inches. Use the awl to punch a hole through each mark.

Step 15:

Here comes the “FUN” part. Punch a hole in the end flap. Put the flap up at the start of the first ramp. Using the awl, punch a hole through the original hole, and then through the side of the box. Push a brad through both holes and have the head of the brad on the inside of the box and the spread legs on the outside of the box.

Using the awl, push a hole toward the bottom of the slanted line, this will let you know where the slanted line ends. Push a hole through the original bottom hole and through the back of the box. Fasten with a brad. Repeat the process with the rest of the whole in the ramp. Then add the other 3 ramps the same way.

Step 16:

Not done yet. Turn the box on edge so that the top of the first ramp is on top. Use the craft knife to cut a square hole through which the marble may be dropped onto the first ramp.

Step 17:

At this point I realized that I forgot something. Something was needed at the bottom to keep the marbles corralled after they finish their race. By then the spray paint was gone so I just cut a 2½ inch x 1 inch (6.25cm x 2.5 cm) piece of cardboard and used the masking tape to attach it to the front of the marble race, on the bottom and the side of where the marbles stop. Now it is done

Step 18:

I will have you know that we had fights over who got to put marbles down the marble race. Oh goody, another chance to teach taking turns and sharing. Enjoy!