  The ages of the components in very short period pre-main sequence (PMS)
binaries are essential to an understanding of their formation. We considered a
sample of 7 PMS eclipsing binaries (EBs) with ages 1 to 6.3 MY and component
masses 0.2 to 1.4 Msun The very high precision with which their masses and
radii have been measured, and the capability provided by the {\it Modules for
Experiments in Stellar Astrophysics (MESA)} to calculate their evolutionary
tracks at exactly the measured masses, allows the determination of age
differences of the components independent of their luminosities and effective
temperatures. We found that the components of 5 EBs, ASAS J052821+0338.5,
Parenago 1802, JW 380, CoRoT 223992193, and UScoCTIO 5, formed within 0.3 MY of
each other. The parameters for the components of V1174 Ori, imply an
implausible large age difference of 2.7 MY and should be reconsidered. The 7th
EB in our sample, RX J0529.4+0041 fell outside the applicability of our
analysis.
