Where is Elizabeth City's cleanest water? Which antacid actually has the least acid? Which can be flung farther: a baseball or a tennis ball?

Those are just some of the questions local middle school students set out to answer with their science projects during recent school science fairs.

Justin Falls/Daily Advance (ENLARGE)

Justin Dobie, 12, (right) explains the principles of a trebuchet, a type of catapult he designed and built for his science project, at Port Discover in Elizabeth City Thursday afternoon. Nine students from River Road and Elizabeth City middle schools who had the top entries in the recent science fairs at their respective schools displayed and explained their projects at the local science center Thursday afternoon.

Winning projects from science fairs at both River Road and Elizabeth City middle schools were on display at Port Discover on Thursday. Standing alongside were the young scientists who completed them.

Candace Stevenson, a science teacher at River Road Middle School, said students had to pick a topic, complete the research, form a hypothesis, conduct experiments and record their conclusions. She said the topics correspond to each grade's curriculum and the bulk of the work is done outside the classroom.

"It really challenges them in terms of the actual steps," she said.

The projects fell into four categories: biology, environmental science, physical science and technology. Several students chose topics which affected their lives.

Seventh-grader Jon Copeland, for example, conducted acidity tests on five different antacids to see how they compared with lemon juice, which is highly acidic.

"My granddad has stomach problems a lot," said Copeland, 12, who hoped to be able to recommend an antacid to his grandfather.

He said baking soda was the least acidic substance he tested.

In some cases, the students' findings ran counter to their initial hypotheses.

Anna Beth Robertson, an 11-year-old sixth-grader, predicted pea plants would grow best if watered with pure water. She tested her findings by watering plants every other day for two weeks with pure water and solutions made from liquid and powder laundry detergents. She said the plants watered with the liquid detergent grew the most.

Robertson said she wasn't sure what caused the outcome.

"The detergent did say it had no phosphates in it," she said.

Seventh-grader Justin Dobie, 12, built a trebuchet and used the catapult-like device to launch different sized balls. He then measured the distances a tennis ball, golf ball and baseball were able to reach when the trebuchet was tested with different counterweights.

"I thought the baseball was going to go farther," he said. "I was totally off."

Dobie said the golf ball traveled the farthest, something he attributes to its light weight, compact size and aerodynamic dimples.

Dobie, who spent about a month building the trebuchet, had a very simple reason for choosing his topic.

"I just kind of like throwing stuff," he said.

Students with winning science projects across the district will get a chance to represent Elizabeth City at the 2008 Northeast Regional Science Fair. The event, sponsored each year by the North Carolina Science Teachers Association, will be held Saturday at East Carolina University in Greenville.