If you were looking for a car to bring your kids to soccer practice in, the Prelude shouldn't have been your first pick. It's a sport compact, not made to have plenty of room.
However despite this, I believe I have seen a cup holder modification that changed the armrest into 2 extra spots for cups.
Ah, here it is.
Aside from that, all I can really think of is to move the seat forward, or backward, depending on if someone is sitting in the back.
Cheers