Mentos + Diet Coke = Explosion! Why?

In our Science class, we've been reseaching about our experiments. I've been reseaching about what's inside the mentos that cause the reaction. I'v found out that it's the arabic (Coating) and gelatine that cause the reaction. Also that there's little holes on the outside that the bubless like to spawn. Right when the mento hits the coke, the carbon dioxide in the coke react with the mento and bubbles start to fom on the mento. The bubbles from so quickly that it forces them upwards and hen fly right out of the bottle.
For my experiment I am using 3 Bottles of Diet Coke and three kinds of mentos. I am using a regular mento, then usin a normal mento again, but taking the shell off of it to see the difference of the explosion. The I am using a non branded mint, (Scottish Mint) to see the difference between the regualr and (fake) kind of mints.

Now we have to come up witha list of materials that we will use during our experiment. I've already came up with my list today.

1. 3 Bottles of Diet Coke (2L)
2. Mentos
3. Non-branded mentos (Scottish Mints)
4. Mop
5. Bathtub
6. Ipod (To record/Pictures)

Variables:
My controlled variable is: The bottles of Diet Coke

My Independent variables are: The Three different kinds of mentos

Procedure:
1. Gather the materials for experiment.
2. Set Up 3 Bottles of Coke side by side inside a bathtub.
3. Set 1 of each mento in front of a Bottle.
4. Take Cap off Bottles.
5. Drop each mento in the bottle it is beside.
6. Stand back and record the explosion!
7. See how much coke is in each botle and visually measure them
8. Mop up floor if any soda got out of the tub.