You need: a small container ( we used an old dishwashing bottle but a coke bottle would do great too)
Warm water ( about enough to fill half the bottle 6 or so drops of dishwashing soap
about 4 tablespoons Bi carb soda
1/2 cup of vinegar
a tub to stand it in and sand to hold it in place and to make the volcano.
Dinosaurs to make it look authentic ( although not really needed)
I got my 4 kids ( yes I gained an extra for today) to create the volcano, being careful not to get sand in the top of the bottle. Once it was in place and looking volcanoish, I filled the bottle with the warm water, drops of dishwashing liquid, and bi carb soda. I also red food colouring to make it looks really lava-ish.
Then, pour in the vinegar quickly and and watch it work!!
Ok, our first attempt was a dismal failure. Not enough vinegar, not enough bi carb, kids thought it was hilarious that I had been so excited and all I got was a tiny bit of froth.
So, with each time we tried it ( and believe me, we went through a whole bottle of vinegar!) we got more game with the amount of bi carb and the amount of vinegar till we got it to properly explode ( its not too high, dont worry) and then run down and cover the dinosaurs below. Jared absolutely screamed with laughter at this experiment. In fact, everytime he told someone about it, he got the giggles and his little face lit up :)
Jumeirah and I talked about how things react, different chemicals cause different things to happen. The soap in the water didnt do much. The bi carb reacted with the vinegar. Its simple stuff but as she gets older we can really get into it. In the meantime, its a really fun thing to make your sensory tubs "come alive!!!"