It depends upon what type of sports and under what lighting conditions.
If you want to photograph an active sport in daylight conditions, just about any digital camera will do the job.
If you want to photograph an active sport in low light or indoor lighting conditions, there are no low cost simple cameras that can pull that off. The cheapest camera you will find, start at about $400.
So, what age kids are we talking about and what sports are involved?
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Had a cannon digital from Best Buy Electronics hated it. Camera is in the repair dept. more than I got to use it. I am not technical savvy so need something easy to understand.

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