This are nice shots and you should consider taking your photography to the next level!
If you don't have a flashgun, then get one as soon as you can. It will transform your indoor flash shots. You can angle the flashhead and "bounce" the light, off a neutral coloured wall or ceiling, or even from a reflector. Or a white sheet.
Shot no. 1, very pretty girl... lighting a little harsh. Watch the highlights don't burn out. Reduce power of the flash and/or add a little negative exposure compensation. Minor niggle, you have "chopped" the end of her plait.
No. 2, nice group shot, I like the little girl's expression on the left! but the background shadows are quite harsh. This is where a flashgun would help. Try not to chop off hands. Consider arranging the girls so that they are not all facing the camera straight on. Have them move away from the background if you can as the background is too sharp.
No. 3. Nice shot of this pretty girl! I like the diffused background and the angle of the girl to the camera.
These are only my opinions but maybe will give you things to think about, you may not agree!
Kind regards
Julia
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