Did you ever read “Horton Hears a Who” or “The Giving Tree” to your children and wonder if they really absorbed the messages of activism, selflessness and giving those beloved children’s favorites preach so gently and creatively? The success of “Kids Who Give,” an on-going contest that recognizes volunteerism by children 7 to 17 would seem to indicate kids are getting the message – and acting on it.

In September 2011, more than 38 million young people ages 16 to 24 participated in volunteer activities, according to the Bureau of Labor Statistics. The bureau doesn’t track volunteerism by people younger than 16, but the “Kids Who Give” contest website (www.kidswhogive.com) has fielded thousands of hits since its launch in 2010, says Jennifer Meetz, director of marketing for Farm Rich, which sponsors the contest.

In 2011, contest winners ranged in age from 7 to 17. Their volunteer and activism efforts included raising money and awareness for local food banks fighting hunger, raising money for children born with heart defects, and founding an organization that supports education for girls in Africa. Each winner submits an entry in which he or she answers the question “What does the phrase ‘giving back’ mean to you?

“To me, ‘giving back’ means to return to society what it has given me,” 16-year-old Rujul Zaparde of Plainsboro, N.J., wrote in his winning entry. Rujul cofounded a nonprofit organization that builds tube wells in Indian villages. “Giving back is creating opportunities for others, so that they too can experience what I have … we have an obligation to help those who have less.”

“Giving back is essential to a healthy community,” wrote Mariah Reynolds, 12, of Cincinnati, whose volunteer efforts include founding three organizations that support veterans and active service members, provide hats, scarves and gloves to children in need, and collect used MP3s and iPods to give to sick children. “There is so much that we can all do and so many ways to give back, that no matter how you explain it or what you call it, it’s the right thing to do.”

“These young people are just inspiring, and there are so many like them out there who have yet to be recognized for all the good they do,” Meetz says. “It’s our honor to recognize and celebrate these amazing kids, and we’re humbled to help them share their stories and experiences.”

The third annual “Kids Who Give” contest is underway. First, second and third place quarterly winners earn donations of $3,500, $1,500 and $1,000, respectively, for their charities. Honorable mentions receive $250 gift cards. A grand-prize winner, to be chosen through a public online vote in January 2013, will earn $10,000 to donate to the charity or charities of his or her choice. The contest is open to U.S. residents age 7 to 17.

To enter, kids should log onto www.kidswhogive.com and submit a 250- to 500-word essay explaining their volunteer work and how it has helped others. You can find full contest rules, details and deadlines on the website. Or, join the conversation on Facebook or follow @kidswhogive on Twitter.