RE: bad landing plane HELP
A wheels landing refers to touching down on the main wheels (under the wing's leading edge) first. As the plane slows down it must then rotate to either the front nose wheel or rear tail wheel, depending on which one it has. If the nose rotates down, toward the nose wheel, the angle of attack - the angle the wing's leading edge is pointed upward relative to the wind - is reduced and therefore the lift is reduced and the plane stays on the ground. Which is what you want while landing.
However, if the plane has a tail wheel, as the tail drops, the main wing angle of attack increases, increasing lift and the plane raises back into the air if it is going too fast. Which is dangerous because suddenly you are too high and too slow and a hard bounce or crash is pending if you don't get back on the throttle to fly out and try again. Many planes have been totaled when the wing stalls and the plane spins in from just a few feet above the ground. I see this happen just about every week. If you give it down elevator you must quickly reverse to up elevator to prevent another hard impact - pilot induced oscillation occurs as you chase the plane up and down.
If the plane bounces up while you are learning to land, giving it throttle and going around is the safest thing to do. Do not try to chase it up and down with elevator! For tail draggers the best way to avoid this is to land on the main gear and hold the tail up so the main wing stays level as it slows down, eventually the tail will drop by itself. Generally, if the tail can't hold up the rear end of the plane, the main wing can't hold the plane up in the air either, and the plane stays on the ground. This is why I mentioned landing trim is important because if you have the elevator out of trim or CG too far back, it becomes very difficult to make a smooth landing.
If you watch an experienced flier take off a tail wheel plane, you will notice the tail comes up and the plane rolls on the main wheels for a short period of time. A wheels landing is reversed. This is why trainers have nose wheels and the kit manufactures sell so many tail wheel planes.