Who will win the first $50,000 Science in Action prize, sponsored by Scientific American? This award, offered as part of the 2012 Google Science Fair, will recognize a student project that addresses a social, environmental, ethical, health or welfare issue to make a practical difference to the lives of a group or community, and that could possibly be scaled. In addition to the cash prize, the winner will get a year of mentoring support from our volunteers (see judges and mentors list) and will get to fly to the finalist awards event at the Google campus in Mountain View, Calif.

Each of the 13 teens below has come up with an amazing idea to help make a difference in people s lives. Eight of them address concerns about providing safe drinking water (collecting, desalinating, purifying). Three focus on ways to improve crop yields. Two are ideas to bring telemedicine to people who don t have easy access to doctors using nearly ubiquitous smart phones and cell networks. To me, all 13 are winners already.

Watch for the formal announcement, scheduled for June 6, of the Science in Action winner, along with the 15 finalists of the Google Science Fair. More information is at the Google Science Fair Web.

And now, meet the finalists and their projects:

Flouride Removal with Renewable Bioadsorbents

Anjan Venkatesh, 14, Bengaluru, India

Fluorosis, caused by ingesting too much fluoride in drinking water, is a problem in developing countries such as India. Although a small amount of fluoride is beneficial to avoid cavities, too much can cause health effects from pitting in teeth to weakened bones.

Adsorbents that are currently used to remove fluoride are either too expensive or need to be constantly replaced. Anjan sought to remove fluoride from water with biodegradable composites, such as a starch/glutaraldehyde and pectin/cellulose/glutaraldehyde, that could readily be renewed, or recharged, after their depletion. Anjan calls himself a science enthusiast and a die-hard dreamer.

Vertical Multi-Level Farming

Sumit Singh, 14, Lucinow, India

Designs for Vertical Muti-Level Farming, which grow crops on two or more levels, have typically focused on urban areas. But rural farmers who work on low-yield or small fields also could benefit from increased production.

Sumit s low-cost design uses only the materials abundant in rural areas and available cheaply such as bamboo, ropes and baked mud tiles. The increased crop yields, of at least 66 percent in experiments, would also offset the investment to build the levels. Shade or part-shade plants would work best for the ground level. Sumit says science is not just my passion, it s my life.

Bioremediation with Agricultural Waste

Geoffrey Tanudjaja, 19, Singapore

Chemical contamination of wastewater affects many developing countries. One remediation technique removes toxins with specially treated agricultural wastes such as sugarcane bagasse. But sugarcane bagasse is only available in tropical countries. Geoffrey s project focused on whether treated grasses, abundantly available in countries that have arid climates and four seasons, could work as an alternative.

Geoffrey pretreated grass with different concentrations of sodium hydroxide to test its efficiency at adsorbing copper contaminants. Geoffrey s interest in science was kindled when his bought him his first science book, A Hundreds Thousands Whys, as a gift for his seventh birthday.

Hydroponic Method for Subsistence Farmers

Salkiwe Shongwe, 14, Siteki, Swaziland

Bonkhe Mahlalela, 14, Simunye, Swaziland

Swaziland subsistence farmers about 60 percent of the total population can t always grow enough crops to supply their entire family until the next harvest. So Salkiwe and Bonkhe developed what they call a Unique Simplified Hydroponic Methods (USHM), which uses simple techniques and available village waste materials, to grow crops in large quantities within limited space without using soil as growing medium. They compared typical subsistence farming methods and their USHM by growing lettuce and baby marrows using the two methods over eight weeks. The USHM increases population of crops in a given area by more than 140% on average. In addition to speeding the time to harvest, the simple USHM eliminates tilling, a cause of soil erosion.

Salkiwe says Asking questions and finding answers is my way of life. Salkiwe and Bonkhe that Bonkhe s family situation, shared by most rural families in Swaziland, can change for the better through science. They hope that, by empowering Swazi subsistence farmers with such knowledge of simplified hydroponics, producing organic crops, Swaziland can be a better place to live.

Smartphones for Early Detection of Cardiovascular Risk

Carlos Vega Garc a, 13, Las Palmas de Gran Canar a, Spain

Cardiovascular disease is usually diagnosed with multiple tests. But to detect risk, it is not necessary to perform all tests; it is enough to have some facts and know physical activity. Carlos developed two sensor prototypes, both of which can detect various physical activities. One was in the heel of the shoe, for physical movement, and the other around the wrist for temperature.

The idea is that, in a more advanced design, such sensors would be worn for a few days and transmit the information collected wirelessly to smart phones. Ultimately, Carlos would like to make an app for Android that would analyze the data received from the sensors and provide a diagnosis. Carlos enjoys museums, chess, and building and programming LEGO Mindstorms.

Seawater Purification Program

Menna Abdel Gawad, 16, Riyadh, Saudi Arabia

Menna sees desalinating seawater as a way for her native Egypt to be less reliant on the Nile for all its drinking water. To get the energy to distill the seawater into potable water, she experimented with solar panels, gasification of incinerated waste and anaerobic digestion, which is the decomposition of organic garbage to methane gas by yeasts and special bacteria.

She says her research suggests that anaerobic digestion is preferred to get energy to purify seawater; solar panels were too expensive and gasification presented a pollution risk. The methane gas that anaerobic digestion produces is then burned to produce thermal energy to boil the seawater in distillation.

Remediation of Perchlorates with Sunflowers

Mark Liang, 14, San Marino, U.S.

Mark s work was inspired by a 2011 article in the Los Angeles Times that said multiple water sources were closed due to the presence of the perchlorate, a chemical originally used in rocket propulsion. He also learned that sunflowers can absorb many types of mineral ions through their root cells in a process called phytoremediation, and this ability has made useful for removing a variety of deadly metals and radioactive materials from the soil. So he decided to see if sunflowers could naturally remove perchlorate from his community s soil. He added a perchlorate solution to the roots of seedlings grown using hydroponics.

Analysis showed that levels of this chemical in the hydroponic medium dropped drastically. (For his research, he used a 0.05 percent sodium perchlorate solution instead of the more toxic potassium and ammonium perchlorates used in the aerospace industry.) Mark says his passion is the natural world, and he is especially interested in how we can use nature to advance technology and modern society.

Effects of Magnetic Fields on Cellular Systems

Andrew Chen, 14 Beaverton, U.S.

Much of our population lives in the constant presence of magnetic fields from electrical devices. Many claims surround the health effects of the fields. On the one side, consumer items such as magnetic braces and jewelry claim (without evidence) health benefits. On the other, if those fields have a negative effect on cellular systems, we could both remediate them from human presence and perhaps use them for cleaning water supplies by killing bacterial contamination.

Andrew s study found that magnetic field strength did appear to inhibit growth of his test colonies of Escherichia coli. He got the idea of treating water with magnetic fields from learning about MRI in the show Becker ; he wondered about the possible deleterious effects of magnetic fields. Then he saw a documentary about people who do not have access to seeing clean water and put the two ideas together.

Design and Evaluation of a Cell-Phone Compatible Telemedicine System

Catherine Wong, 16, Morristown, U.S.

In developing countries, or remote areas without access to quality local healthcare, it may be difficult to travel to a doctor. Today, however, cellular networks are nearly ubiquitous, even in areas lacking other basic infrastructure providing a platform that could put local medical care directly in the hands of patients who need it most. Cell phones, which are common even in developing countries, could be used to help with the basic screening and monitoring of chronic ailments such as cardiopulmonary disorders.

In her work, Catherine designed and evaluated a cell-phone compatible, Bluetooth-enabled electrocardiograph prototype capable of transmitting an EKG image for remote examination. Her device used a Bluetooth-enabled wireless transmitter with a microprocessor programmed to read the EKG output for display on the cell-phone, and instrumentation amplification circuitry to amplify cardiac electrical activity.

Catherine says that engineering is applied dreaming. She enjoys tinkering and has a provisional patent on telemedical designs.

Pani Purification

Sabera Tulukder, 15, U.S.

Sabera sought create a water-purification system that cheaply and portably purifies water for third world countries. She named it Pani because it means water in Bengali, which is where her father s family lives. Her three-stage system starts with a burlap bag and copper or brass mesh filter. The second step is using a solar-powered ultraviolet (UV) light to kill bacteria. Last is a barrel of activated carbon to filter out the membranes and organelles of dead bacteria.

Sabera says she has many passions including sports (especially swimming), theater, clubs, Web based teaching, school, and the community. Her favorite class is AP Physics, and she volunteers on weekends at the American Cancer Society Discovery Shop.

Investigating Natural Postemergent Herbicides

Grace Brosofsky, 16, Buford, U.S.

Weeds choke the output of crops, causing billions of dollars of losses in food and in costs, but how can we safely get rid of those plant pests? Grace tested 14 solutions of natural herbicides, including such compounds as clove oil, vinegar, d-limonene- (extracted from citrus), lemon juice, and a yucca extract/garlic extract solution. She focused on postemergent efficacy weed control for already-growing plants.

Grace is particularly interested in chemistry, because it serves as a foundation to other sciences, and enjoys playing piano, reading, swimming, volunteering, scrapbooking and spending time with her family.

Collecting Rainwater in Used PET Containers

Ricardo Enrique Alba Torres, 17, Bogat , Columbia

Jessica Bibiana Alba Torres, 15, Bogat , Columbia

Even arid areas can benefit from collecting rainfall for drinking water and other purposes. A brother-and-sister team, Ricardo and Jessica, developed a tank wall with PET (polyethylene terephthalate) plastic containers for rainwater harvesting. They say reusing bottles saves 40 percent of the costs of using current collection systems.

Ricardo loves playing tennis and soccer and Jessica enjoys listening and singing to music, dancing, playing sports, and reading news or articles about advances in technology, culture and science.

A Solar Powered Water Purification System

Katherine Zimmerman, 16, Bradenton, U.S.

Water covers about 70 percent of our planet, yet most of it is not drinkable. Katherine built a solar-powered water purification system that included an active solar still with evaporator and condenser stages to increase water productivity, compared with using a passive solar still. She collected information about performance with sensors and her own software. She was inspired to build the system after seeing people who have difficulties getting enough water during summer travels with her family.

Apart from school and science fair, Kathering dances ballet, plays piano and violin, and speaks Russian, French and Spanish.