Can't get focus right

[oldschool65]

I'm attempting to take photos of my sons' lacrosse games; however, most every shot focuses on the trees or people in the background and not the action on the field, even when my sons are in the middle of the frame (or at least close too it).

I'm a total novice and am lost when the camera is set on anything other than an auto-set mode, but I'm certainly willing to adapt and practice with manual settings if that is what it will take. I am using an Olympus E-500 set to "sport mode" with an Olympus Digital 40-150 mm lens.

Any help would be greatly appreciated, as I am missing out on some great shots.

[Jimmy B]

Welcome oldschool, check out in your manual for the camera if you can change the focus point too the center one in the camera. If your camera has a "P" mode try using that and the center focus point. I hope that gives at least a starting point to try, Jimmy B