That's pretty harsh. My wife got to keep her company TSX whilst on mat leave, twice. Can you imagine if you were a single parent and your employer took away your only form of transport, nightmare... 
My daughter was born in July, and because teachers are technically only employed for Sept-June, she lost all her mat benefits as she was not employed by the board at the time.
So she got EI, but no top-up, which was a LOT of money lost.
Then, to make it worse, they used to claw back EI benefits if you earned a certain amount in the period after your mat leave, and so we not only received no pay or benefits from the board, but ended up paying back all the EI.
Well, you have no one to blame but yourself.

With better planning, you could have had the teacher go on mat leave right at the Christmas break. At least that's the hope for me... of course, 'junior' looks like he might make his appearance before the missus is done school so we might be out a couple of weeks' of my wife's pay too.

Giving up a company car?! Ha! I'm just happy that we'll save mileage and fuel costs by her not doing the 1:15 hr commute each way for the year!