I doubt you are going to get it all picked up. Honestly, if you are doing construction around there the grass will get torn up anyway, maybe get a friendly farmer to come over and plow or disk up the yard and then run over it with a box blade or scraper to smooth it back out, this should bury the majority of the glass and other construction trash that is too small to pick up. Then once you re-plant the grass it should hide or cover anything that is left.A distant future problem is all the broken glass in our old yard. But we have a year to figure that one out. They are safe from eating any glass right now.