In 'search' box at the top of this page, enter mushrooms. More info than you might want is available there.

I am 99% sure you have puffballs. If left alone, they might grow to the size of basketballs, or larger. Or they might only grow to that size. There are many species. All are edible (and prized) when young, although I never tell my kids that any mushrooms are edible, even if I know they are. When they grow older, I can teach them what to eat and what to avoid. When the insides of puffballs turn brown, they are mildly toxic (I think, a strong laxitive). There is a 1% chance they are the very young stage of a regular mushroom, in which case I have no idea what species or toxicity.

Here is a link that might be useful: Giant Puffball Mushroom

puffballs, I mow around them when I get them...

Some people like to hit them with their golf clubs...