The lab is written so that students must give some thought as to the procedure, which I generally have to help them with, because they are so use to following canned experiments. I then solicit volunteers to mix up and standardize the acid. The class then proceeds with the titration. They soon find out that the endpoint is not sharp and well defined. We then discuss procedural modifications that will take care of the poor endpoint.
Students then repeat the lab.
A lot can be taught with this laboratory investigation. This of course will be a disaster because of the insoluble product calcium sulfate.