The present invention provides systems that allow reliable multiplexed transformation of Drosophila embryos. The present invention provides methods and reagents that allow preparation of injection-quality nucleic acid samples and that allow simultaneous preparation of multiple such samples. The present invention provides systems for simultaneous processing of multiple injected embryos. The present invention provides methods for transformation of Drosophila embryos involving use of virginator strains that can be used to increase the efficiency of setting up the crosses needed to produce the eggs for the injections and for the crosses needed to screen for transformants.