Is it “childish” to rhyme in poetry?
I don’t think so. I actually prefer poems that rhyme because they keep my interest intact. If it’s short and it rhymes, then it would sound childish to me. I think it’s also about the matter. If it’s about serious issues, then it can still rhyme and it wouldn’t sound as childish as maybe rhyming about your favorite something. I’ve read lots of poems written by great authors that rhymed and they didn’t sound childish at all. Whoever told you that “no good poems rhyme” was obviously lacking in something important. It’s harder for me to sit and read a poem that doesn’t rhyme because I’ll rush through them and there’s no beat in it, so it’ll just sound like a story or a bunch of words. Poems that don’t rhyme have to evoke some feeling for me to continue. I say go for it and rhyme away. Good luck!