Not a good idea. The yard will be a messy potpourri of weeds and wild flowers with the weeds winning again. Best way to go is to hire a pro to weed the yard, condition the soil and plant the proper type of grass for your growing conditions. Even planting wildflowers requires special preparation of the soil, many believe one just sprinkles the seeds around and that's it. I am assuming in giving you this answer assuming that the yard had a grass bedding which was taken over by weeds. If not, a photo of your situation would help.

Hi, welcome to GoY, what sort of wild flowers would you like to grow, what you call 'weeds' are wild flowers, probably just not the type you want to grow.
Was your yard concreted, and the weeds are coming through the concrete ? or do you have a flower bed across part of it, and if it's a raised bed, is the concrete still there under the soil?, Derek.
Hi Loosestrife, in the U K, when someone says their yard, it usually means that it 's a small, usually walled area, which once contained the toilet, usually the width of the house, and extending 10 to 15 ft from the house, I know that in the U S A it means your garden, but not so in the U K, Derek.

Not unique to the U.K. D. I lived the first twelve years of my life in a cold water flat with no inside toilet. Yup, I know those kind of "yards" too.

There are plenty of garden plants that help bees too Lisa. Could you add a photo to your question so we can see the site? As weeds are just plants growing in the wrong place its quite hard to answer without a bit more info. (eg celandines and clover are wild flowers but in a garden can be weeds as they spread wildly. And some wild flowers like a bit of shade and some prefer full sun.
If you can't fine the "add a photo" option you can post the question again with a pic or two.

Are you wanting to plant it and leave it to get on with things without further care or are you thinking of looking after it - it affects what plants are recommended. Sun or shade, and what area are we talking about?