You will have a hard time with mouse embryos, as ex utero culture is not easy. However, cell lineage tracing in the mouse is now so much easier using the inducible Cre recombinase and a Rosa26 reporter gene. There are many promoters available that give tissue specific expression of a tamoxifen inducible Cre, once tamoxifen is given at a low dose to pregnant mice, a specific cell population can be tagged by the induced Cre and all progeny will then express the reporter gene. There are many papers using these systems in mice to do lineage tracing.