okay my birds are parakeets as i have mentioned, she will not sit on eggs?

"Infertile Eggs

One possible cause for infertile eggs is that the hen laid the first clutch too soon, before the cock mated with her. Try blocking off the nest box for a few weeks, then allow her to lay a second clutch and see if they have better luck.

If the male is an English budgie, make sure the feathers around the vent are not so long that they cover the vent, preventing insemination. If the feathers are too long, trim them carefully with scissors, leaving the down showing around the vent.

Make sure all the perches are stable and do not wobble or roll.

If the pair produces two clutches of infertile eggs, remove them from the breeding cage and consider trying them with different mates or waiting until a later date to try again.

Eggs Thrown from the Nest

Make sure there is a concave area in the nest so that the hen can sit on all the eggs without any of them getting away.

If the hen is young (one or two years old) refrain from breeding her for another year. Hopefully she will lose the habit with maturity.

If the hen continues to discard her eggs from the nest, replace her eggs with dummy eggs or white marbles. After she incubates these for a week or two, remove them and allow her to lay another clutch hopefully she will have lost her egg-throwing habit.

If egg tossing continues to be a problem, you can use her to foster other chicks, but you won't be able to breed her."

http://www.budgieplace.com/breeding.html

Maybe she hasn't had sex with the male yet. Sometimes females lay eggs and toy with them. Parakeets are sometimes uncomfortable about having sex but if your female is laying unfertilized eggs, throw them away after the female is done playing with them (a couple of days) My female, Kelly, laid her first egg. It never hathed but she was trying to practice how to sit on them when I gave the eggs to her.