NHL 11

Achievement is called "Supposed to be Standing" . It's for scoring a goal while on the ground or on knees. 2 player method works here. You can have a friend pull their goalie and let you get a breakaway before you let them trip you so you can drop on your knees. Once you are on your knees, you'll have an empty net to fire at and the achievement will pop.

The quickest way to get this is to set up a local game with extra controllers in Play Now. Put all the guest controllers on the other team. The more controllers the better, so if you have 3 extras use them all.

When the game starts, pull the opposing team's goalie with back + LB. Now circle back with the puck toward your own zone so the players controlled by the guest controllers bunch up in the middle of the ice.

Now skate toward your opponent's empty net and one of the AI controlled players should be following very close behind you. Just after crossing their blue line, hit RT on any of the guest controllers to take control of the guy trailing you, and immediately hit LB + RB to dive. This should drop you to your knees and now just shoot on the empty net.

The most difficult part about this achievement (for me at least) when attempting with friends is aiming and timing the dive in order to knock the other player to his knees. I found this method to be more reliable in that sense because the AI who will be diving is in the exact position necessary to accomplish this. Finally, having more guest controllers makes it easier for you to isolate one AI player rather than having a bunch of them swarm on you as you cross the blue line.

Supposed To Be Standing
Score a goal from the ground or your knees

This one is easiest done while boosting in a ranked versus or online HUT game. Simply have the opponent pull the goalie and pull all of his defense away from you so you can get a breakaway. Then slow down and let the opponent dive at you with LB + RB and you should fall to your knees. Shoot it into the empty net. This might take a few tries because sometimes your guy just wont fall.

Thanks to acdougla17 from 360achievements for this solution
http://www.xbox360achievements.org/forum/showthread.php?t=25...

The quickest way I found to do this was to first lower the penalty slider to zero in the gameplay settings then lower all the goalie sliders to zero and raise the player puck handling to 100 too and choose the easiest difficulty. With that setup any time you get a breakaway the D will trip you but no call gets made so you can keep trying, and since the goalies are slower its easier to deke around while on your knees. If it helps try taking someone with a good handling rating, Crosby or Gaborik are the top I think. I was able to unlock it in my first game playing with this setup. Good luck

If you're not a fan of boosting or manipulating the gameplay settings you must know that this feat is very possible to achieve naturally.

Two things to keep in mind once you go down.
1. Don't deke like you are standing up. Either go forehand or backhand and shoot.
2. Shoot quickly, you literally have no time to pull this off as it is and I find the quicker the shot the better your chances are of lighting the lamp. I also find going with backhander works best.

Good luck.