What was it that the teacher (Olivia) was teaching them about the volcano on the island?

Was it volcanic ash that Locke came across while on his way to Jacob's creepy house?

This island is of volcanic origin and the volcano is long dormant. The Barracks is built over the now filled-in main tube, as we saw from the panoramic shot in 3x1 and also Danielle's maps. Besides the cone, there were also vents in other parts of the island. This is what the teacher's diagram showed. It was a pertinent science lesson for the kids.

http://img172.imageshack.us/img172/5158/lessonht1.jpg

The one thing about her blackboard drawing I did'nt understand is the shape she drew above the left vent. It's marked "lava", and it looks like a crude outline of a bunny:) It looks interesting. I wonder if it's a birdseye view of their part of the island, with the small circle representing the cone?

I was more concerned that, on this island, you can add water to bicarbonate to get a fake volcano. Everywhere else on earth, you need to add an acid, like vinegar. Maybe the woman can't have children because of acidic corrosion of their insides from the water . . .

That is very interesting riccool, I did not catch that. I had assumed the teacher was talking about baking POWDER, not soda, since I had no idea what bicarbonate is, but I knew baking powder does react with water.

Maybe the volcanic eruption killed the civilization that built the four-toed statue?

what if the disturbance in the house was simply the volcano's activity and Ben really is crazy

P.Stones

Bicarbonate is like Alka Seltzer. When you add water to it, it fizzes.
Its baking soda that fizzes when vinegar is added.