When I was growing up, we just worried about cuts and scrapes. Now it seems my grandkids have friends with all sorts of conditions. Latest one is psoriasis. I've never heard of that.?

Chronic disease. Psoriasis is a chronic recurring autoimmune skin disease with a strong hereditary component. Can appear as large scaly patches affecting only certain parts of the body (ie: elbows, knees, scalp, hands, feet, nails) or the entire body. It can be mild to severe, be triggered by stress or other factors. Can be treated with topicals, oral meds, biologics (injectables), light therapy.
Psoriasis. Psoriasis is quite variable. There may be dense, silvery scales on the scalp. Knees, elbows. Sometimes it is trivial. Sometimes it is extensive & disabling. It may involve nails & joints. It can be very depressing. Psoriasis can appear only in those born with the genes for it, but it may first appear at any age. There is no cure, but we are not helpless. Your dermatologist will help.