Everything from playing games to diapering and feeding children is part of a child-care worker's job, which is to provide a nurturing and safe environment for children in their charge. They may work in their homes as family day-care providers or in child-care centers. There are 2,150 licensed child-care centers in the state and about 11,000 licensed family day-care providers.

SALARY: Nationally, lead teachers average $15,000 annually while assistant teachers average between $8,000 and $10,000. In Boston, the average hourly pay for lead teachers in centers is $9.92 an hour; for those in family day care, $6.77. By contrast, Boston's public school kindergarten teachers make an average of $32.15 an hour.

EDUCATION: Educational requirements vary according to position in a day-care center.In Massachusetts, an assistant teacher must be 16 and have a high school diploma. A teacher must be 21, have a high school diploma and have experience and/or education in child development, which may be a Child Developments must be certified.

Professors at colleges and universities teach and advise students in their academic specialties, develop curriculum, and continue their own study and research.

SALARY: Average for nine-month contract, $65,440, full professor, $30,830, instructor.

EDUCATION: A doctoral degree is usually required, although a master's may be sufficient to teach in some disciplines or at two-year schools.

Librarians find, organize and disseminate information to a vast public, from the corporate executive to the third grader working on a school report. Librarians also may be called information professionals. The computer, with extensions such as the CD-ROM, has become one more tool in the librarian's arsenal, changing his job dramatically. Indeed, there are now cybrarians - professionals who help those lost in cyberspace find the information they want.

SALARY: New librarians start with salaries in the low $30,000s in the Boston area; corporate offers can be $10,000 higher. National average for reference librarians in large-sized libraries is $35,079; for children's librarians, $35,845.

EDUCATION: The basic degree is a master's; in many states, school librarians must be certified teachers as well.

Called teacher's aides or education assistants, these people assist the in classrooms. They may do everything from helping in the lunchroom to reinforcing instruction in small groups. Aides generally work in elementary schools, and often with special needs students. They are gradually finding a place in the upper grades.

SALARY: Nationally, instructional aides earn an average of $8.70 per hour; non-instructional aides earn an average of $8.29.

EDUCATION: There are 15 states that have certification requirements for paraprofessionals; Massachusetts is not one of them. Rhode Island has recently implemented minimum standards. High school is generally required; some college helps. Each school district, even each job, has its own requirements and on-the-job training is common.

Principals run schools and superintendents run school districts. They are the administrators of the education system and they do everything from talking to parents to hiring teachers. They help set the goals of a school or system and implement policies and procedures to achieve them. Their jobs include budget preparation, teacher training, student discipline, and curriculum development.

SALARY: $60,922 is the average for elementary school principals across the country; $69,277 is the average for high school principals. Superintendents earn an average of $94,229.

EDUCATION: A principal in Massachusetts must have a graduate degree in educational leadership, significant experience and be certified. Further education and certification is required for advancement.

These are the people in the classrooms who help kindergarteners practice small motor coordination and high school juniors understand trigonometry. They monitor students' progress and use appropriate teaching methods; they may also design new approaches or educational materials.

SALARY: $42,174, for Massachusetts public school teachers; $36,874 is the national average.

EDUCATION: A bachelor's degree is required and teachers must be certified. Certification in Massachusetts requires specific courses and a practicum; for those applying now, it also requires a master's degree. Continuing education is mandatory and recertification is needed every five years. Education reform is changing requirements in many places throughout the country; a master's degree may be required elsewhere as well.

DEMAND: School systems in Massachusetts are hiring now as education reform takes firmer hold. In addition, the school population is growing, particularly at the high school level. At the same time, the number of retirees is increasing. While the need for all teachers is expected to grow, high school teachers, especially in math and science, will be in more demand. Special needs and bilingual teachers are in great demand.