As mentioned, many pullets/chickens have to announce to the world that they have laid a daily egg and they do it by screaming: 'Bok, bok, bok BA-BAWKKKK' Over and over and over! It may have something to do with complaining about a sore vent from squeezing out an egg day after day, but it can not be stopped. You can do as some people do and leave them locked inside the coop until after lay time is over (About 2/2:30 pm) but that would be very cruel in the summertime to be locked into a stiffling building. Could also be fatal depending on where you live. You need to bear in mind that the birds need good ventilation year round also and that means that humidity as well as sound can escape.
Chickens are not nearly as loud as an annoying neighborhood barking dog so your neighbors may be able to sleep through the noise on the weekends. I have read that laying times are from about 10 to 2/2:30, but sometimes mine lay even earlier than 10. Another thing to consider is that some breeds just simply tend towards being more noisy as a rule. What breeds are you working with?
I think my best suggestion is to just give them a good solid coop with a nice chicken yard and let them live out their chicken lives and if you get complaints, sell the noisier birds and try to replace them with breeds known to be calm and quiet. They still may make the chicken laid-an-egg song.