The factory jack, which is stored under the passenger's seat, will lift
a RAV4 tire off the ground if the correct lift point under the vehicle is
used.  You should not need to use a board or other extension to use
the jack.  The exact lift points are vaguely pictured in the owner's manual.
The lift points are the shape of a small tab that fits into a corresponding
slot on the lifting surface of the jack.  These points are not on the
frame of the vehicle, as on most cars, but on the suspension.

In the front, the lift points are behind the wheels, slightly to the rear of the
wheel center.  In the rear, the lift point is several inches in from the edge 
of the body just forward of the rear wheel.

On sensible suggestion is to find the lift points at a convenient time and 
then clean and paint them a bright color.  That will make finding them at
a less convenient time easier.