The number one thing we grow every year JUST for chickens, is kale.
It's very nutritious and they love it. We either pick a bunch, hold it by the stalks and they pick from it, hang it in the coop so they have to jump up to get some, or lay it in the yard with a brick on the stalks.
We put down stakes and used chicken wire around our garden. That does keep the chickens out of it and usually the rabbits too.
We too don't like to plant much and yup, most goes to weeds anyway, but corn, sunflowers, squash, pumpkins, kale, always, and sometimes radishes, carrots, and beets. The tomatoes get blight so bad here so I bought a grow light and going to try those from inside the house this year, never putting them out.