 CERT-TESOL Certificate in Teaching English to Speakers of Other Languages CERT-TESOL is an internationally recognized professional teaching qualification that is common in the field of teaching English as a foreign or second language. The course is designed for potential teachers with little or no classroom experience and is therefore considered an entry-level qualification in English language teaching. CERT-TESOL courses can be taken in a variety of locations as they are individually organized and designed by different language institutes worldwide. Each of these course providers is regulated and certified by Trinity College London. The CERT-TESOL certificate is seen as equal to the CELTA certificate due to the similarity in the course syllabus.