I have a little one with severe hand eczema and I have a personal care plan written for him.
It talks about his individual needs - washing in Diprobase, monitoring drying, wearing gloves for messy play, using sticks instead of fingers, not playing with salt as it is too drying, regular application of Diprobase through the session etc.
I have a son with chronic debilitating eczema and my theory used to be to let him get on with it at other settings and manage the skin as best as possible when he got home.
However, this parent is very different from me and worries about every crack and lump and obviously I have to work to her. So I do my best to make sure his skin is not further damaged during his time with me.