Twenty high school students are enjoying the new iPads they earned by reducing their carbon footprint and writing a great essay about it.

The students were part of an essay contest held by the Regional Transportation Commission of Southern Nevada, Coca-Cola, Mariana's Supermarkets and the Clark County School District.

The 20 winners were chosen out of the 200 entries from 40 high schools around the Las Vegas valley. They all wrote a 500-word essay describing how they used transit services provided by the RTC to reduce the amount of carbon they personally use.

The winners for the 2013 contest are:

A group of local middle school students wants southern Nevadans to be aware of what they call an environmental hazard at Lake Mead.

Greenspun Junior High School Leadership Club students are launching a public campaign about “the dangers and the damage done by the use of carbureted 2-stroke engines.”

In 2013, a ban on personal watercrafts with carbureted 2-stroke engines went into effect to help reduce pollution at the lake. Leadership Club students, led by educators Gwendolyn Buckles and Katie Litzenberg, started an educational campaign named “Lake MEad.” It focuses on the effects pollution has in southern Nevada’s public recreation areas.

The students created a multimedia campaign to spread the word about the 2-stroke engine ban at the lake. During their after-school club, students chose this cause as their annual community project.

The student who most accurately guessed the time that Mojave Max would emerge met the desert tortoise, during a visit to his habitat Wednesday.

Fourth-grader Kayla Marshall of Gehring Elementary School was joined by her whole class in the visit to the Red Rock Canyon National Conservation Area Visitor's Center.

Besides meeting Max, the students got T-shirts and a pizza party. She also received a digital camera, a laptop computer and free year-long pass to federally managed lands.

Kayla missed the actual time that the tortoise would emerge from his burrow by only two minutes. Max left his burrow at 1:45 p.m. March 14. He had been in a state known as brumation, which is the reptile version of hibernation, since the fall.

When the weather warms up and there is more daylight, the tortoise makes his way out of his burrow. It is considered one of the most accurate signs of spring in the Mojave Desert.