Weird Science

A while ago, we were talking about the increasing flood problems in my 7th grader class when I asked the students to name other types of natural phenomenon that can be disastrous.  There was total silence.  Nobody could name a single one.  I listed some on the board, and they just gave me blank looks.  This wasn't surprising.  Their knowledge really doesn't extend the limits of Mongkol Borei.  They can't point out various locations in Cambodia on a map, let alone find another country.  Once, I asked a student to point to England, and he just stared at the map in confusion.

I decided it was time to do some cross-curricular lessons, and what better place to start than volcanoes.  Why volcanoes?  Well, they are totally cool, and teenagers like to see stuff blow up.  I taught them the definition of volcano, explained the vocabulary such as lava, steam, ash, explode, etc, and showed them videos on youtube of volcano eruptions.  They drew pictures of volcanoes.  I showed them pictures of the time I went volcano-boarding, and described the experience.  They couldn't believe that people do such a thing, but they thought the scar on my leg was impressive.  I asked who would like to go volcano-boarding, and three students raised their hands (all girls I would like to add). 

Then, it was time to make a volcano.  When I told them we would have to go outside because it was going to make a big mess, they all cheered and ran down the stairs.  I explained that the Coke bottle was the volcano, and the Mentos was the lava.  I opened the bottle and threw in about 8 Mentos.  The results were good.  The soda exploded, and the kids had the opportunity to witness the power of Mentos. 

Afterwards, I gave each student a Mentos candy (which they have not tried before), and told them to eat it.  They were hesitant.  I think they were afraid their mouths would explode.  I popped one in my mouth to show them that it was o.k.  One boy sniffed his first before warily putting it in his mouth. 

Another day, I asked the students, "How can insects walk on water?"  They looked confused, and thought about this.  One students said, "Because they are lighter than the water?"  I said, "What about those spiders that walk on water?  They are heavier than the water." 

I pulled out a paper clip, and told the students to pretend it was an insect.  I asked several of them to try to make the paper clip float on the top of the water.  They tried, and of course, it just sunk to the bottom.  I told them that I could make it float.  They were skeptical but curious.

I cut a small piece of tissue, placed it on the water, put the paper clip on top, and then slowly pushed the tissue down.  The paper clip remained floating on the top.  They were astonished.  I asked, "How is this possible?"  No one had a clue, so I explained about "surface tension."  They took notes, and we discussed the vocabulary.

Then, I let the students try the experiment too.  They all wanted to try, and thought it was great.