Jennifer Lopez -- Please Admit My Twins to Your School!

Jennifer Lopez is experiencing the kind of stress that hundreds of rich L.A. mommies endure every year -- getting their kids into exclusive, VERY EXPENSIVE private schools.

We've learned Jennifer has been making the rounds in L.A., interviewing schools for her 5-year-old twins, who will be starting kindergarten in the Fall.

We know she went with kids in tow Tuesday to the famous Buckley School in the San Fernando Valley ... considered by many to be the best L.A. has to offer. By the way, it better be -- tuition and other costs total $33,345 for the year -- PER KID!

And when we say Jennifer was interviewing ... she's the one -- like all the other parents -- who had to put on some snazzy clothes to impress. Lots of very rich, very famous parents try getting their kids into Buckley.

Alums include Paris Hilton, Nicole Richie, Matthew Perry and current student Paris Jackson.