Why doesn't my household vinegar make calcite fizz?

I am teaching a unit to 4th graders on rocks and minerals. I really want to show them how calcite can fizz by dropping vinegar on it, but the vinegar at my house isn’t working and I don’t know why. Is it because it is 5% acidity? Is there a special kind of vinegar to use? I remember doing this test in my undergrad geology class so I know what is supposed to happen, it’s just not happening.