copyright 2009, The Washington Post WASHINGTON -- It's tough enough selling military service to teen-agers who might not be so keen on getting their heads shaved or buy the whole 'we do more by 9 a.m.' line. And the fact that enlisting today could very well mean a visit to the front lines doesn't help, either. But according to a new report, there are other factors that make recruiters' jobs even more difficult: the country's poor education system and the worsening obesity crisis. About 75 percent of the country's 17- to 24-year-olds are ineligible for military service, largely because they are poorly educated, overweight and have physical ailments that make them unfit for the armed forces, according to a report issued Thursday. Other factors, such as drug use, criminal records and mental problems, contribute to what military leaders say is a major problem that threatens the country's ability to defend itself at a time when the all-volunteer force is already strained fighting two wars. To combat the problem, a group of retired military leaders has joined Education Secretary Arne Duncan to call for greater investment in early education, which advocates say helps boost academic achievement and social development. 'We are very concerned,' said retired Army Maj. Gen. James Kelley, a member of Mission: Readiness, the Washington-based nonprofit organization that issued the report. 'We do have the greatest military in the world -- we have the greatest planes, the greatest tanks, the greatest ships -- but the key goal is having great people. Right now, we're attracting very highly qualified folks but that could change over time.' The report, 'Ready, Willing and Unable to Serve,' comes after the military had one of its best recruiting years since the draft ended in 1973. During the budget year that ended Sept. 30, the military met all of its recruiting goals and had a higher quality of recruit than in years past. About 95 percent of all Army recruits had a high school diploma, up from 83 percent the year before. Military officials say their recent success is due to increased spending on recruiting and bonuses, which in the Army went from an average of less than $8,000 in 2000 to more than $18,000 in 2008. A dismal economy, which drove up civilian unemployment, helped fill the ranks as well. But in its report, the group warns that 'a weak economy is no formula for a strong military. Once the economy begins to grow again, the challenge of finding enough high-quality recruits will return.' One of the main reason recruits don't qualify for the service is inadequate education. One in four between the ages of 17 and 24 does not have a high school diploma, according to the report. And many who do still fail the military's version of the SAT, known as the Armed Forces Qualification Test. Asthma, eyesight and hearing problems are also factors. But about a third of all potential recruits can't join is because they're too fat and out of shape. 'When you get kids who can't do push-ups, pull-ups or run, this is a fundamental problem not just for the military but for the country,' said Curtis Gilroy, the Pentagon's director of accessions policy. Many kids are not 'taking physical education in school; they're more interested in sedentary activities such as the computer or television. And we have a fast-food mentality in this country.' Recruiters, then, become part-time tutors and coaches, helping with homework and whipping kids into shape. Some even hold after-school workouts, where teen-agers prepare for basic training. To pass an Army physical fitness test, an 18-year-old male must do 42 push-ups in two minutes, 53 sit-ups in two minutes and run two miles in 15 minutes 54 seconds. Earlier this year, the National Guard opened a 'Patriot Academy' in Indiana, which helps high school dropouts earn a high school diploma after graduating from basic training. In Maryland, the majority of Guard recruiters are also certified substitute teachers, helping recruits with their homework, said Sgt. Maj. Anthony Weeks. 'We'll go work out at the gym with them to get them in shape,' Weeks said. But that's become increasingly challenging. Nationwide, more than one in four adults is classified as obese by the Centers for Disease Control and Prevention. Mission: Readiness, which comprises 89 retired military leaders including two former chairmen of the Joint Chiefs of Staff, is pushing Congress to pass the Obama administration's Early Learning Challenge Fund, a program that would grant states $1 billion annually for 10 years for early childhood development programs. Educators say preschool programs are one of the best ways to ensure academic success later in life. Military officials think they're one of the best ways to ensure the country has a large pool of people who will be savvy enough to fly helicopters, drive tanks and gather intelligence. 'You can't wait until high school in order to change a young person,' said Kelley, the retired major general. 'It has to be done at a very early age, and that's why the need for high quality early learning is so vital.' 