I have had a lot of luck with these barrel jumps. First of all you can move them and mow under them which is super nice. So you take those big plastic 50 gallon barrels and saw them in half length-wise (circular saw works great). You need two barrels to make this work or one if you want a narrow jump. It is fun to have different color barrels. Anyway, lay the barrels down and bolt them together length-wise. You drill holes in the ends. I generally have to clamp them together to do this or have a friend help you hold them together. I use three half barrels. So you can lay these on the ground now or you can add height. I then take 2x4s probably around 2'5" and again bolt them to the ends of the jumps at an angle to make it more stable. I wish I had a picture to understand this. If you are really interested let me know and I will go out and take pics. I have lots of these jumps on my property.
If you use 2 barrels you will have one half left. You could always make a ground feeder with this. Put two 2x4s (pressure treated) parallel to the half barrel with the open of the barrel upward. I would probably bolt them or just screw them in. I would also drill some holes in the bottom so the water would drain out.
I get my barrels from a car wash in town. I like them b/c it is just soap in them. We have lots of scrap would around our house from an old play ground for the braces. I generally don't have problems with bees/wasps making nests in these either. Not sure why?