Go for the calamine creme over the lotion. The aqueous creme also helps.
Icicle, how old are you? I'm 34 and I had a triple jab - MMR - I didn't know anyone growing up who had measles, mumps or rubella. In fact, my 38-year-old sister had an MMR jab as well. My folks has all these diseases, but they're in their 60s.
Never heard of deliberately exposing kids to it, either. A classroom setting is usually enough to spread it around.
And you're right, Stella, it's extremely rare to get chicken pox twice. What can happen to those who have had chicken pox is that they can get shingles. This, however, normally happens to people w/compromised immune systems - such as the elderly or those with chronic illnesses, taking anti-rejection drugs, etc.