what do you need to be a teacher?

It really depends what type of teacher you would like to be. However the main pathways are generally the same and the options vary but go along the same lines.

1. You need to graduate high school.
2. You need to attend a college/university and earn a four- year B.A. degree. You will want to get a bachelors degree in the subject-matter that you want to teach, this makes certification in your state and subject-area feasible. You may opt to minor or double-major in education. You do not need to have a bachelors in education to be a teacher. I would suggest getting a bachelors degree in the subject you would like to teach. (for example: I am an English teacher, I majored in English literature and now have a bachelors in English).
3. Once you graduate college with your bachelors degree you have a few options:

A. Go directly to Graduate school and obtain your masters in the area of teaching/education you want to teach (ie. Masters of Education, Masters of Teaching, Masters of Secondary English, Masters of Teaching in Secondary English, Masters of Teaching in Elementary, Masters of Special Education etc.). You may also opt to get a masters degree in the subject-are you wish to teach. However, while in graduate school you must obtain a masters degree in some variation of teaching/education. So you will have either a MAT (Masters of Teaching) or MED (Masters of Education). Most graduate schools have one of the two programs and offer a variation depending on the subject (ie. Masters of Teaching in Secondary English or Masters of Education in Secondary English). This option is ussually a fifth year pathway that allows you to student teach at a school while earning your masters degree.

B. You can apply to an Alternative Route to Certification (if you state has options/offers this). This would look like a program like TeachForAmerica, AmeriCorps TutorCorps, or other Teacher Residency Programs (ie. KIPP Teaching Fellows, MATCH Schools, or charter schools that offer Teacher Resident positions. Look up the options in your state or the options available if state is not a boundary for you. During the year or two-year commitment of these programs you would typically also have classes or being earning a masters degree. This option is for teachers who want to start working directly after they graduate college. Some programs lead to Certification in your state and others lead to BOTH Certification and a Masters Degree. The ARC programs lead to 90 day certifications, which then lead to Initial Educator Certification OR Resident Teacher Certification (ALL are pathways to FULL certification in your state).

1. Regardless of which route you take you will need to take the certification exams in your state. MOST states, including CT (which is the information I know because it is my state) require the PRAXIS exams. You will need to research certification requirements within your own state for more information. However, while you are earning your masters (or after you have earned your bachelors) you will want to also prepare for and take the PRAXIS Core (which can be waived if your SAT/ACT scores are high enough) and the PRAXIS II which cannot be waived and MUST be passed for certification.
2. Once you have obtained your Bachelors degree AND Masters degree AND Passed your state certification exams AND done some form of students teaching (whether that is during college or in a residency program) you can then:
3. Go to your state board of education website and complete your certification information.
4. Then, you can APPLY as a LEAD teacher in the area you are certified.

MOST pathways take 4-6 years. You will be able to start your first year of teaching as a lead teacher generally in year 5 or 6.

To expand upon my previous answer, here are more details on the Praxis exam. The PRAXIS is a series of exams that are taken to enroll in a graduate teaching program and to obtain teaching certification in most states. There is the Praxis Core which is a more general exam/standardized test. It covers math, english/reading, and various subjects similar to the ACT & SAT. Some teacher prep programs and graduate programs require the Praxis Core, others do not. Most programs will take you SAT or ACT scores instead. Also, if you get above a certain score on your ACT or SAT your Praxis Core can be waived even if it is required. Then, you have to take the Praxis II (which is ussually taken during your graduate course study for your teaching degree, or during your ARC (alternate route to certification) program, but it can be taken before the programs or passed after your receive your degree. Most programs will require that you take it at least once during the time you are getting your degree, but you MUST pass the Praxis II in order to become a certified teacher. The Praxis II will be taken according to the subject you wish to obtain your certification in. You need to do research according to the sate you live in and the program you are doing as well as the field of study you are getting your certification in. For example, I am a secondary ELA teacher so I had to take the Praxis II (5039) Content & Analysis. This is similar for other secondary ed teachers, but they wil take it in their own respective subjects. In contrast, elementary teachers must first pass the Praxis foundations of reading test. Then they have to pass Praxis subjects tests in various subjects.