How old are the kids?
Could you call the store you bought the fish from to find out the names? The names are essential in figuring out what could've caused the problems. Any idea what kinda catfish you had? There are not a whole lot of commonly available catfish that are good to go in a 10 gallon tank.
Did you cycle your tank before putting fish in?
What do you mean by normal temp? Normal is a relative term. Considering there is such a wide range of temperatures that different types of aquatic critters prefer normal can refer to a lot of things.
A tip of advice: Always research fish indepth before buying them to make sure you have the means to properly care for them.
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http://www.fishlore.com/WaterChemistry.htm http://www.fishlore.com/NitrogenCycle.htm