Shooting a HS game this upcoming friday and was wondering if I can make this work to get some non blurred images. HELP!!!!!!!

its a canon 100-400 mm IS, I'm a little concerned about the iso only being able to go up to 1600 is that going to be a show stopper or what. Beginner any comments will do.

Is it a night game? If so, that's going to be tough.

Looks like the Rebel XS only goes up to ISO 1600...
http://www.dpreview.com/reviews/canoneos1000d/3

Unless the stadium has NFL HDTV-level lighting, even with the ISO maxed out and the aperture wide open on the 100-400, you're going to need more light.

Do you have a speedlight (flash)? If so, no problem... you can shoot ISO 1600 and f/5.6 but the subject will need to be within flash range.

If it's a day game, no problem.

Moved to the correct gear board

you could try a better beamer flash adapter.
In the end your f 5.6 will be very limiting for night sports even with a newer camera. I would think most experts use something like the 400mm 2.8 in order to get a good shutter speed.

No. It just plain is not going to work. Texas takes its HS football pretty seriously and most fields are more well lit than (the national) average. To get the shutter speed necessary to stop action it is strictly a ISO3200 and F2.8 proposition. And that is between the 20 yard lines - it is darker nearer the end zones. The laws of physics are a bitch.

I shot a HS playoff game in the new Dallas Cowboys stadium and it was ISO1600 and about 1/800th-1/1000 at F2.8. That's about the most well-lit venue you are going to find, and you would be at 1/200 to 1/250th with your gear. Too slow to stop action.

If you need some proof I have about 13,000 HS football images online.

If you will be doing this going forward your best bet is to find a nice used 1D Mk3. If you have full access (can go anywhere on the sidelines including in the players/coaches box) a 70-200 F2.8 is a good place to start, and pretty cheap if you get a good used non-IS model. (The IS doesn't help you much). When playoffs come you will NOT be allowed in the box no matter how tight you are in with the team, so at that point you rent a long F2.8 lens like a 300 or 400.

There is a reason why 10 people are not already successfully shooting your HS team night games - the minimum required equipment is a significant investment that most parents are not willing to make. And there is a not a real strong commercial incentive to do it either.

Good luck!

EDIT: Yes, you could do it with flash. Do you have an off-camera flash cord? At minimum you will need a cord, a bracket system to mount and aim a flash below the camera on a monopod, and at least a 430 flash and a 550/580 would be a lot better. If you don't own the cord, for about what the cord will cost you plus all the other hardware you can just about rent the non-flash gear you need. And if it is your first time shooting night football with flash you will probably end up with more keepers shooting with the non-flash setup.

If you don't have a local mentor there are lots of threads here with suggested cFn settings of the camera you would rent, or images of a good flash setup and recommendations on settings.

Jump in and try it, and good luck!

Moved to the correct board?

Well with that setup your not likely to be able to freeze the motion. However that doesn't mean you can't get any shots. Even with a longer shutter speed, you can get some creative shots, even panning along with the action. You won't get a lot of keepers, but you might practice that technique to get some interesting shots.

As mentioned, see if you can use a flash as well.

I shoot with a 7D using a EX430 flash at 1600 and f5.6 with no problems.
I currently do not have a 100-400 but shooting the 70-200, 5.6 is 5.6