I found a little pre-exam prayer. Reword it into your own 'speak' and use it.

Prayer Before an Exam

Dear Lord,

Sometimes I feel a little strange praying
to you because of an exam.
It doesn't really seem all that significant
when you consider the "big picture."
But right now, the test looms so large
that it is all I can see before me.

I pray to you for three things:
- the strength to handle the pressure that I feel,
- the confidence to feel secure
in my knowledge and preparation,
- and the ability to keep an appropriate
perspective on it all.
Help me to keep in mind what is really important,
even as I focus all of my time and energy
on this test in the immediate future. Amen

(www.jesuitnola.org)