Early Clone Question

I'd like to grow one plant in a scrog method but don't want to spend all my time screening up 3 different plants just to find out that two of them are males.

Is it possible to speed up the process and get into flowering within three weeks just to find out what sex they are, then take some clones off the female and start fresh with one of them?

no... either use a sure female clone, or feminized seeds.. or bite the bullet and screen all 3 ...

as soon as your plants can be cloned do this:

1) one clone of each plant.
2) put it in a 12/12 area.
3) the clones die in 2 weeks but will show sex just before they dye.