Thanks for the suggestion. I will do some experimenting and see if I like the results better.

If they open the blinds the light would be on the right side of their faces.
To focus 1/3 to 1/2 way into the field do I need to leave my camera on single shot focus and use the center point to focus on someone at that distance?
Yes I could sit on the edge on the stage.

Kids sit on the floor. Many times we get them up to do different movement type activities. In those pictures I usually change the setting to Sports because I figure that is a better setting for when they are moving. I've tried TV and not had very good results at all. Not sure what I am doing wrong there. I know that the shutter is staying open to long but when I've tried to increase it I still don't have good results. Maybe I am not increasing it enough. Tried a couple of times to up the ISO but then the pictures were to grainy. Decided at that point to stick to one or two modes because I was getting confused on what I had tried. Everything moves to fast for me to take a notebook in and write down what I've tried. We only have about 20-30 minutes on those mornings so we move pretty fast from activity to activity.

When I want to focus on one or two students I use f2.8 usually. When I am trying to get more of the students in focus that seems to be when I am having problems. Those up close to me are in focus and I would like them to be. That is why I was asking about a different lens.

The stage is probably four feet higher than the gym floor. We do have some windows on the north side and they have blinds which are closed most of the time. I will look through some pictures and see if I have a good example to post. I usually delete those like I am describing so I don't know if I saved any. The rows go across the narrow part of the basketball court. We have pull out bleachers but we don't use them because they are old and hard to pull in and out.

I shoot in aperture mode.

I have taken pictures in the gym before but what I find is that many times the kids up close are out of focus and I don't like how that looks. That is why I was wondering if I needed a different lens. We have a stage and where the kids' rows start is only about 5-6 ft. away and I can't go back any farther without getting on the stage and I'd rather be at eye level. The lighting (fluorescent) isn't great but most of the time I can keep my ISO at 800 or lower when they are on the gym floor. If they are on the stage that is another story.

I am sorry that I didn't respond to the tripod question. Yes I have both a tripod and a monopod that I can use.

It started out as just taking my camera to school to learn how to use it and has turned into so much more fun than I ever imagined!

We have about 270 students and they sit in class rows. That would make about 14 rows. I don't necessarily need to get all 14 every time but I would like to be able to get 100-150 kids max in a photo. I figure that would still be close enough to be able to recognize the faces in the first four or five rows, don't you think?

I know you are all knowledgeable and I need your help with choosing the right lens. I am a teacher and take tons of pictures at school. Inside and out. Friday's we have a morning meeting with all of our students and we do a number of different activities and I try to take advantage of those times when we have all of the kids together. I have the Canon T3i and need some suggestions. I would like a lens that I can take pictures that will give me a good depth of field as well as sharp near and far and side to side so I get a large number of the kids in the pictures. Sorry for my lack of technical terms. I have the standard kit lens that came with my camera. Do I use it and just use f22 aperature with a higher ISO since the lighting isn't great or is there a lens that would work better for my gym situation. I hope I am not offending those of you that have "been there done that" when answering this question a million times.
I also have the Canon 24-70 f2.8 IS lens. Is this a better choice? If so what settings would you recommend with this lens.
I am envious of all of the knowledge everyone has on this site and was hesitant to ask because I didn't want to expose my lack of knowledge. But, I want to improve my photos and know this is the place to go and learn from the best.
Thanks in advance for your help.

I've been to Glacier three times and you are right. It is one of the most beautiful places you could ever see. Haven't been there in a number of years but Hidden Lake is another beautiful spot to take pictures. Took some up close and personal pictures of mountain goats on that hike.

I did the same thing to my Canon T3i. I ordered the new screen off ebay and my husband watched a Youtube video and replaced it for me. Minimum charge from Canon was $180 and he did it for the cost of the new screen, $6.99. Check out Youtube and ebay.

Thank you for the information. I wondered how to tell how much PP you should apply. This will be helpful.

You have all been so helpful. I will go back and set my camera to neutral and work with that for a while and see if I feel I need to make adjustments.
So much to learn!!!!