back in paris in 1837, he returned to the conservatoire, but became assistant professor of reicha then holder of his own class created by cherubini, the director of the conservatoire de paris. elwart held the post until his retirement in 1871. among his pupils were louis-aimé maillart, , théodore gouvy, jean-baptiste weckerlin, émile prudent, olivier métra, edmond hocmelle, adolphe blanc, albert gisarn, victor frédéric verrimst and oscar comettant who described him as "an ingenious and witty scholar". it seems that he had a good relationship with his pupils, the latter ironically calling him "little father elwart".