After evry rain, my backyard is a giant swamp. Behind the pool where the
ground slopes there is always a giant puddle. The rest of the lawn you can
not really tell it is swampy until you walk on it.

Any ideas as to how to fix it? Should I level out the yard with new dirt and
grass seed, or just dig a drainage ditch?

Also if I till the yard, level it and add new grass seed, how can I do that
and still allow my kids to play in the yard?

Thanks,
Frederick