Four students hope an initiative by former U.S. President Bill Clinton will help launch their plan to use landscaping to remove contaminants from vacant lots in St. Louis. Another wants to make inexpensive prosthetics with a device almost small enough to fit into a backpack. Two others want to launch a smoking quit line in China.

All have proven that their ideas are viable enough to participate in an unusual gathering at Washington University this weekend.

A thousand students representing all states and 75 countries will take part in the sixth annual Clinton Global Initiative University, aimed at tackling such global challenges as education, public health, environment and climate change, and human rights.

The agenda includes a session Saturday night between Clinton and Stephen Colbert of Comedy Central’s “The Colbert Report.” Panels involve people such as Jack Dorsey, the co-founder of Twitter, and Muhammad Yunus, who won a Nobel Peace Prize for his efforts to eliminate poverty.

The event will conclude Sunday with a volunteer project at Gateway STEM High, a magnet school in St. Louis that emphasizes science, technology, engineering and math education. There, volunteers will paint and do other improvements to the grounds. Later, 100 solar panels will be installed on the school’s roof to reduce energy costs and provide a renewable energy teaching tool.

“I especially like doing things in and around schools that have a community impact,” Clinton said in an interview with reporters Tuesday. “I like Gateway STEM because it’s committed to raising the level of STEM knowledge and involvement among kids that often get left out and left behind.”

This weekend’s meeting is an outgrowth of the William J. Clinton Foundation, which Clinton began in 2001. The foundation, based at Clinton’s offices in New York, has a number of initiatives aimed at domestic challenges such as job creation and childhood obesity, as well as global issues such as climate change and worldwide poverty.

The event will have an emphasis on empowering women and girls worldwide, preventing prescription drug misuse and promoting STEM education. Chelsea Clinton will moderate one of the panels.

The three-day event is modeled after the Clinton Global Initiative annual meeting, a nonpartisan convention held each fall of global, business and philanthropic leaders to work on solutions to world problems in areas such as the environment, energy and health. The university version takes place at a different campus each year. Last year it was held at George Washington University in Washington.

To take part, students needed to pitch action plans. The Clinton Global Initiative selected the students based on their projects.

Washington University Chancellor Mark Wrighton said the conference fits well with the school’s focus on community service. “This is a conference that is not only stimulating great ideas about how to address the world’s problems, but, most important, it is a venue to learn how to implement these great ideas,” he said.

Of the students taking part, 200 are from Washington University, including Ian Smith, an undergraduate and Iraq war veteran whose portable 3D printing device could potentially provide 3 million amputees worldwide access to artificial fingers and limbs.

Funmilola Oladini is a pre-med student whose plan is to educate health advocates in her Nigerian hometown about diabetes and hypertension — diseases that are increasing as fast food restaurants proliferate there.

Both see the weekend as a chance to tap into networks and funding that could otherwise be out of reach.

“This is huge,” Smith said. “I consider myself lucky whenever I can contribute to the world or society at large.”

This year’s program in St. Louis will include more than $400,000 in available funding for students to carry out their commitments, through a network of 32 colleges and universities that have provided seed money.

“There will be a lot of interesting ideas that if other people with more resources and a bigger network would take up it could literally have a profound impact on the world,” Clinton said.

In 2010, a group of Vanderbilt University students pitched their idea at the initiative’s meeting at the University of Miami in Coral Gables, Fla. One of them, Kyle McCollom, a graduate of St. Louis University High School, laid out a plan to start a custom T-shirt company that would employ former criminal offenders from a halfway house in Nashville, Tenn. Three years later, Triple Thread Apparel has created more than 30 jobs and job-training opportunities and sold over 20,000 shirts, McCollom said.

To host the meeting, Washington University needed an action plan of its own. The university will invest $30 million over six years to reduce its greenhouse gas emissions, Hank Webber, the university’s executive vice chancellor for administration, announced last week. The aim is to scale emissions back by 22 percent by 2020, reverting to 1990 levels.

The cuts would come through better waste management, new heating and cooling, and greater energy efficiency. It would pay for itself in eight to 10 years.

“This takes what we’re doing to the next level,” Webber said.

Clinton said his hope for the initiative is that students leave the meeting believing they can make a difference in areas they feel strongly about.

“Having all these young people come to CGIU, it may be more inspiring for them to be around each other than to have me there,” Clinton said. “I want them to imagine that they can actually have an impact, that their ideas count, that their deepest concerns are things they can actually act on.”

Kevin McDermott of the Post-Dispatch contributed to this report.

Lewis and Clark County and the Helena Chamber of Commerce are hosting a Green Business workshop Thursday, April 4, at 10 a.m. to educate business people in the community about sustainable landscaping options.

Dennis Flynn from Valley Farms will explain the benefits of commercial landscaping, the most inexpensive form of advertising and biggest hello to customers. He’ll offer ideas for reducing water and pesticide use.

The green business workshops are offered the first Thursday of each month in 2013 and are associated with the Green Business Program, a free certification program in the tri-county area that recognizes businesses for their sustainability efforts. To learn more and get your business certified, visit www.greenbusiness

mt.com.

Water districts throughout western Riverside County will play host to the 11th annual Community Water Conservation Festival on Saturday, April 6.

The free event will be held at the Big League Dreams Sports Park, 2155 Trumble Road in Perris.

The festival will run from 9 a.m. until 1 p.m. A landscaping workshop begins at 11:30 a.m. and the first 100 people in attendance will receive free water-saving items.

During the event, residents can learn about retrofitting outdoor irrigation equipment to become more water efficient and about water-wise landscaping ideas, among other topics. A number of master gardeners will be on hand.

Presentations also will be given on smart controllers, high-efficiency toilets and drip irrigation systems.

Each participating district will have information about rebate programs available to customers and a raffle will be held.

There will be many activities for children throughout the event. A puppet show will be presented at 11 a.m., and there will be face-painting and caricature booths. “Dewie the Dragon,” “Zoie” and “Admiral Splash” will be in attendance to help entertain and educate children.

“This is a fun, community-based event for the whole family,” said Stacy Rodriguez, EMWD’s conservation program supervisor and committee chairperson for the event. “Our hope is that families come out, learn how to be more efficient with their water usage and take those ideas home to help them save water, time and money.”

The festival is presented by Eastern Municipal Water District, Elsinore Valley Municipal Water District, Rancho California Water District, Western Municipal Water District, Metropolitan Water District of Southern California, Bureau of Reclamation, the State of California Department of Water Resources and the County of Riverside’s “Only Rain Down the Drain” pollution prevention program.

For more information on the program, go online to www.iewaterfestival.com.