How do you handle situations around elementary kids whose gender is unclear?

Since our language is so dependent on pronouns, there’s always sentences coming up like “you took his pencil, please apologize to him,” or teachers leaving notes for boys to do x and girls to do x, or to alternate boy and girl for turns, etc.

But lately I’ve been seeing a lot of boys with long hair that I assume are girls until I learn their name, and vice versa, and sometimes girls have boy names, which makes it even more confusing for these situations. So I’m just curious how other teachers approach situations like this when they’re not sure of genders?

Edit: I understand they/them exists but as I explained in some comments, it always feels obvious to me in its usage that I’m avoiding gendered pronouns because I can’t tell their gender, and I didn’t want kids being made fun of because others realize I can’t tell if they are a boy or girl. It seems I may have been overthinking that. The other problems, like when teachers have the kids take turns alternating boy/girl or other things based on gender, are still outstanding questions though