Ok I'm taking the clippings out of my fenced yard for the chicks I gave them a couple of hand fulls shared by 50 chicks so I don't think they got much and they are still in the coup. I figured that it couldn't hurt since it seems that they eat everything else including the wood shavings in the bottom of the coup. I do have sand in the bottom with the wood shavings as well a couple of inches of sand and about 4 barrels of wood shavings. Thanks for the heads up.
As long as you have sand down that they can eat as grit, there is nothing wrong with a few handfuls of grass. Esp. with 50 chicks. I have 16 that are 3 weeks old and they get a handful of grass a couple times a day. They have a pan of sand that I put in there so they could dust bathe. I do try and make sure they are small pieces of grass because it seems to really bother them when they can't get the long pieces out of their mouth.
My chickens were afraid of the mower. I started putting some clippings in the run and now when i mow they stand in the run looking at me like...aren't you done yet, we want our treats. They especially love the st. augustine grass.
I used to feed my chicks chunks of sod - there would be little rocks and sand (to serve as grit) and possibly a worm or bug or two in the dirt part of the sod, and the grass to nibble on, and lots of entertainment for the chickies. Seemed to do just fine.