Teaching is one of the most challenging jobs in the USA— and one of the most vital. According to the Census Bureau, about one in five American children live in poverty, and they face enormous obstacles as they journey through the public school system. Despite these challenges, skilled teachers manage every day to change the trajectory of students' lives.

As the leaders of the National Education Association andTeach For America, we know from experience that great teachers are made, not born. Continuous learning, reflection and improvement are the building blocks of a successful teaching career. Unfortunately, not all teachers are getting the high-quality preparation they need to excel with students in the classroom.

In recent years we have seen increased emphasis on teacher quality and evaluating teacher performance. As a logical next step, we must measure the effectiveness of the programs that prepare teachers. That's why we're glad to see that Secretary of Education Arne Duncan and the Department of Education are tackling this issue head-on with a recent blueprint for teacher education reform.

As the architects of school policy begin implementing this blueprint, we urge them to keep the following in mind:

•Use data to improve teacher preparation. In Louisiana, a state aggressively tackling the question of teacher quality, studies have found significant differences in student outcomes based on where their teachers trained. As described in the Education Department's blueprint, Louisiana is using a three-tiered system to assess whether a teacher preparation program's graduates perform at, above or below the level of the average new teacher. States such as California and Maryland are evaluating programs based on multiple measures, including student, principal and alumni surveys. The common thread is a system for evaluating training programs that prepare teachers for today's classrooms and students for today's information age.

•Bring new talent to the teaching profession. There is an increasing breadth of talent and experience among new teachers — from recent college grads to career-changing professionals — and it is critical that they all have access to high-quality training for a smooth transition into the classroom. One viable path is the proposed Presidential Teaching Fellows, a federal program that would give funding to states that commit to improving teacher training, as well as provide merit-based scholarships for candidates entering teaching through traditional or alternate routes. The Presidential Teaching Fellows places a priority on scholarships for candidates from low-income backgrounds, and also helps recruit and train more teachers of color.

•Give teachers opportunities for continuous professional development. Even after teachers reach the classroom, they need a strong support network and continuing opportunities to hone their skills. The most successful teacher preparation programs recognize this by helping facilitate mentoring relationships with veteran teachers during student teaching and encouraging ongoing professional development opportunities for their graduates. High-quality programs also offer leadership opportunities to their teachers, allowing them to build their skills in areas like curriculum development and peer mentoring. If we expand professional development, new teachers will be much more likely to stick it out past the first challenging years.

One in three K-12 students will be assigned a teacher who is in the first three years of his or her career. As a new generation embarks on a career in teaching, we must commit to giving them the best preparation possible. Secretary Duncan's blueprint is a much-needed catalyst for change. Now schools of education and other teacher education programs must band together and reform practices to better prepare educators for classroom success.

Wendy Kopp is the founder and CEO of Teach For America and the co-founder and CEO of Teach For All. Dennis Van Roekel is president of the National Education Association.