Rohana,
Dancing Raisins (Irish version) is a great prompt for an inquiry. The children can be shown the phenomena and asked to try to explain what is going on in their own words. From that you can pull out a suitable starter question.
They might wonder
- does the 7 up work if it has been open for a day? (and think – not as many bubbles, so no).
- do other fizzy drinks work? (and think – yes, the bubbles are there)
- do other small objects dance – or is there something special about the raisins and try currants, dried apricots, peanuts etc.