Challenging rhymes with:
scavenging, arranging, avenging, changing, cringing, exchanging, impinging, infringing, lounging, lunging, nanjing, plunging, prearranging, ranging, rearranging, scavenging, scrounging, shortchanging, unchanging
Challenging sounds like:
clanging, clanking, cleansing, clinching, clinging, clinicians, clumsiness