I've spent a fair amount of time up in that area, so here are a few more ideas that are off the beaten track that haven't been mentioned yet.
1. Coho Cafe in Tofte. Right off of 61 and they have really good food. I'm a big fan of their wild rice sausage pizza.
2. Judge C.R. Magney State Park - it's North of Grand Marais, and has a really cool waterfall called the Devil's Kettle. It's a bout a mile in, and it's really cool since the water funnels into the rock and it's unclear how it comes out again. Fun for kids (and adults) to think about.
3. Oberg Mountain (between Tofte and Lutsen). It's a decent hike up to the peak with great views. I did it ~10 years ago and remember it as not that challenging.
4. If you're really feeling adventurous and want to get out in a canoe, I'd go see one of my favorite waterfalls on the East side of the BWCA, Rose Lake Falls. You'd travel up the Gunflint Trail to the Hungry Jack area, put in on Bearskin Lake, portage to Duncan Lake and enjoy the falls between Duncan and Rose.
https://www.gunflintcanoeing.com/_wp2015/canoe-day-trips/rose-lake-falls/