Bob, Your Cavalier may not have a dip stick. Transmission fluid is not added or checked like in the old days, there is no fill tube or dipstick. Transmission fluid is added after removing the vent cap (cap normally red) located at the top of transmission by the shift linkage. Do not overfill transmission. There is a fill level plug (may be 12mm hex head) that will have to be removed, plug is located above middle of the pan, to the left of the bell housing, a few inches from the bottom of the housing. With the vehicle at operating temperature on level ground, as soon as trans. fluid starts running from the fluid level/full hole, stop adding fluid and wait for fluid to stop running from hole,reinsert the plug, transmission is full.
I hope this helped you out, if so let me know by pressing the helpful button.
Pic's and further instruction can be seen at attached link. Good luck.
http://www.justanswer.com/chevy/2e38e-2005-chevy-cavalier-automatic-transmission-i-check-fluid-level.html