Mushrooms in your lawn are indeed a sign of a healthy soil. They are the fruiting bodies of fungus living on organic matter in the soil. They ordinarily do no harm to the lawn unless they form a ferry ring. If you find them unsightly, just mow or kick them over. Or you could get your seven iron out and practice your swing if you are a golfer. Spring is a great time to transition into organic lawn care. You may wish to use some pre-M and chemically spot treat for weeds the first year after which there should be no need for chemicals and your lawn will be better than ever. You have found the best place to ask your lawn and garden questions. Do not hesitate. You may also want to checkout the organic lawn care forum.
Bill Hill

Here is a link that might be useful: Organic Lawncare FAQ

I believe mushrooms are the most misunderstood aspect of lawn care. As mentioned, they are usually a sign of healthy soil, which is why so often you find them growing in the earthy forest floor. Yet so many folks think of them as some sort of weed that somehow spread into their yard and needs to be eradicated.

There's a layer of fungus growing naturally in your healthy yard, and from time to time it sends up a sort of "fruit" which we know as a mushroom.

I ignore mine. They don't harm the grass, and neither ignoring them nor kicking them over will make them spread.