ONE YOGURT, FOUR STUDENTS? CERTAINLY
You need a single-portion pot of any yogurt other than French set style. A sachet of jelly crystals. And a 1-pint jug.
The basic principle of jelly crystals is that you dissolve them in as little boiling water as possible. They must be fully dissolved - 30 seconds in a microwave speeds things along. (Don't microwave the spoon.).
Ordinarily, you would then dilute the liquid up to a pint with cold water. For a yogurt jelly, add some cold water to the jug and stir in, but leave enough room for the tub of yogurt as well. Tip in the yogurt -top up to a pint with more cold water if necessary.
Use a blender or mixer to combine until smooth. Put in a bowl or divide between 4 cereal bowls, and refrigerate until set - at least 4 hours. It may separate into layers - this doesn't matter.
HINT: If you keep your milk in a jug, then you have to cover the jelly with a lid or cling-film, or the milk will acquire a fruity taste! (If your milk is kept in a bottle, no worries.)
You can do the same thing using a can of fruit and its juice (but don't use pineapple or kiwi - something about the acid prevents the jelly from setting). Blend or leave fruit whole.