hiː hɐz mˌeɪd nˈoʊɾəbəl kˌɑːntɹɪbjˈuːʃənz tə ðə stˈʌdi ʌv tˈiːtʃɪŋ, ɐsˈɛsmənt ʌv tˈiːtʃɪŋ, ænd ðə fˈiːldz ʌv mˈɛdəsən, sˈaɪəns, ænd mˌæθɪmˈæɾɪks.
He has made notable contributions to the study of teaching, assessment of teaching, and the fields of medicine, science, and mathematics.