The spelling list your child brings home every week can tell you a lot about how they are teaching reading and spelling at his/her school. If the words are following a similar pattern, such as “bat, cat, can, lap” (short-a words) or “nation, vacation, conviction, election” (all “tion” words), then spelling is being taught as a skill that follows predictable patterns and can be learned through word-study.
However, if your child’s spelling list looks more like “autumn, apple, because, doll” and is just random words or a list of sight words that do not follow any particular pattern, then you should be concerned. Your child is being taught that spelling is random and all words must be memorized. This is not an efficient way to learn how to read and spell!
As a side-note: yes, around 10% of English words do not follow the pattern, and these must be learned by rote. But those 10% of words still all have predictable parts and only one or two letters which must be memorized! This should be pointed out to children, and studied using multisensory techniques.
Learning By Design has published this great list of Ten Things Parents Can do to Improve Spelling. I encourage you to take a look!