the t2i comes with the ef-s 18-55mm IS. It is a decent wide angle lens. If you do need to chase kinds around indoor, I would go wit a lens like the ef-s 17-55 2.8 IS USM, or the sigma and tamron 17-50 2.8. They will give better results indoor with the bigger aperture.
Chasing kids outdoor the ef-s 55-250 is okay, but the ef 70-300 IS USM would focus faster on the kids.
Macro, you can go a very inexpensive route. With either the ef-s 55-250 or the ef 70-300 you can add a 500D close up lens and it will let you get some pretty good macro shots. Here are the examples what that 80 dollar conversion lens can do with both those zoom, the ef-s 55-350 first.
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Canon Eos 60D, T1i/500D, Eos1, Eos 630, Olympus EPL-1, and a part time Pentax K-X shooter.