I've worried about this a little despite my kids not being teenagers yet, still some years to go. I've thought a lot about it because I'm on the tail end of being into craft beer(budget has shifted, I'm sure it's not hard to guess where) and it's nuts to me that I have anxiety about them "catching" me vaping when I drink so freely in front of them, at the pool, at the beach, etc etc. To me it should be the opposite but thanks societal norms. Also I live in the California bay area so they've been around it and smelled it in public on a few occasions at the very least.
A couple of years ago before I had re-entered the vaping world I would get my glass pipe out for a friend when he would visit and one occasion I forgot to take it off the mantle and put it away. They instantly zeroed in on it and started asking questions, got me nervous even though I had a scapegoat because their mom(not together anymore) can take issue with things like this(understandable) and she was always not a big fan of cannabis, mostly the smell, induced headaches. But to my complete surprise one of them says, "Mom has one just like that!" So I laughed and said, "There ya go, adult stuff, you'll learn later." And it was solved... for now.
I probably am more embarrassed about my compulsive spending on my vape collection than I am about using cannabis.
I identify with this and it's been an oh so short time for me compared to most here. Ramping down and figuring out what I like most is happening... slowly. Hoping I can part with at least some of it down the road.
*Edit
Apologies for not giving advice, just wanted to offer my own experience. That being said, in my book you're doing fine and you can't hide things forever, usually. On the scale of things to hide from your kids it's both understandable and minor imo. When I was younger I knew some families where the parents never hid their cannabis use and by high school(no idea how early it started) their kids were joining in and there were no boundaries at all. Those families were completely foreign to me and not how I would ever want to handle it in my household but to each their own.