Should Gifted Kids Always Take the Hardest Classes?

I pose this question to you and I truly do not have an answer myself. I'm looking for help with forming my opinion. Should kids always take more difficult classes just because they are gifted?

For example, I have a student who is 99th percentile quantitatively. He asked me today if he could be dropped down to the regular math class. Not because he didn't understand the concepts, not because he could not keep up, but because he really just didn't want to work that hard.

Is that okay? Should we allow them to do that? What do you think? I have wondered that myself for my own children.