This web site loads slowly, but is pretty nifty:
Note: the wording on this website is more vague than the AP test. The AP test always asks for "a 95% confidence interval" if it wants an interval (or some other %). Also, the AP problems are longer, and thus have more information that will guide you to deciding what to do.
However, I think that after you 10 or so of these, you'll get used to the wording of this site and it will be good practice.
Note: this website includes prediction intervals, which you do not need to know.
