i guess you could, but wear it with items that aren't so intense that it makes u look overdressed. if it's hot, a little vest and sandals would do nicely. if ur a little cold [idk where ur from] a casual cardigan and ankle boots would go well =]
My school said as long as it was 3 finger with straps and your skirt is not short than your arms with finger tips it is fine.
In my school it is completely normal to wear skirts/dresses. I think it looks cute. To make it more comfortable at school you could try to eear a grey cardigan and a pretty scarf too it. (Btw there is a lot of inspiration on pinterest to outfits like that👍🏼)