Chemistry classes at the school had recently been learning about chemical reactions and students stepped outside Nov. 1 for a lesson in creating "self-carving" pumpkins.

Halloween screams were heard at Coventry High School, but they were not because of scary costumes or masks.

Chemistry classes at the school had recently been learning about chemical reactions and students stepped outside Nov. 1 for a lesson in creating "self-carving" pumpkins.

The experiment got just the reaction that science teacher Danny Savage expected – screams – as a chemical reaction in the experiment caused a loud bang and flames that left beautifully carved decorations in the pumpkins.

"You expect it (the bang), but it still scares you," junior Hannah Thorn said.

A couple of years ago, Savage was looking for an interesting experiment to show how particular chemicals react and stumbled across the self-carving pumpkin project. The experiment shows that when a flame is introduced to a mixture of calcium carbide and water it produces a combustible gas called acetylene and explodes and burst into flames

"We learned that when you mix the chemical with water it starts to bubble and when you add fire it explodes," junior Caleb Wallace said. "It is a fun project and fun way to learn."

To make the experiment work, students carved pumpkins and replaced all the "cutout" parts so the pumpkin appeared to be uncarved. Savage instructed the students to get some calcium carbide and place it in a small cup and set it in the pumpkin much like a candle would nestle in a jack o' lantern. When told, the students poured 20 milliliters of water into the cup and placed the lid on the pumpkin to let the smoke build.

"The longer you let the smoke build the better your explosion will be," Savage told the kids.

Because of the wind they needed to be extra cautious. They used a relighting birthday candle on a stick to poke through the ignition hole in the back of the pumpkins and when the flame hit the gas inside the reaction caused a small explosion that forced the pieces flew out and flames to light the inside of the pumpkin.

"It smokes up a bit and the fire just makes it blow," sophomore Jimmy Schindewolf said of the experiment.

Students worked in teams of two or more to carve the pumpkins and the team members worked together to make the mixture and create the reaction. Juniors Kayla Jackson and Krissi Bucy designed a pumpkin with K K for their initials and the year 2013.

"It was fun and we learned how the elements, when combined react really big," Bucy said. "I did not expect that."

There was a large variety of creative pumpkins including super heroes, Batman symbols, faces, Hello Kitty and more.

This is not the only fun learning activity Savage has throughout the school year. Earlier this year students melted gummy bears. They heated up potassium chlorate and added a gummy bear in the test tube. The chemical reaction causes as small light show and sometimes cause the little bears to dance.

Savage said the idea is to teach the students chemistry is everywhere.

"I talk about the periodic table and how awesome it is," Savage said, noting that chemistry is in everything from our bodies to table salt. "We talk about the reactions and what will form from certain chemicals and we can always (refer) back to this (pumpkin experiment) because it is something they remember."