My husband and I are considering doing a 3-4 day canoe trip in the Boundary Waters in Early August with our 3 kids -- ages 10, 13 & 15. We have done pretty intense backpacking trips with the kids before (3-4 days with packs on our backs covering 8-12 miles each day out West) but this will be our first canoeing trip. Wondering what a good 3-4 night trip would be to see the best of what the BWCA has to offer. Also, any recommendations on outfitters would be appreciated. We have our own camping gear but would need to be outfitted with canoes and food. Thoughts?

There is a list of outfitters on this site somewhere. West half near Ely, and East Grand Marais. I've used 3 in Ely. They will custom to your specific needs. They have trip planning and permits and canoes and food and lodging and professional advice.
There is a recent thread here on picking an easy trip with postst listing some options.

Welcome, truly hope you will find canoe tripping a nice change of pace from backpacking.
August is still a very busy time of the year so camp sites within a one day travel tend to get taken. I will be doing a 4 day trip in early July and intend to get any decent site the first night then head hard into more isolated areas and base two nights then return all the way out the fourth day. Most folks do not like the longer portages but if you are hikers you could look into something where a little portaging can get you into some nice and less traveled areas. If you have no canoe experience you might want to find a local place and rent one for the day and get a little paddling experience. It isn't all that hard, but getting a little experience can make a big difference as your wilderness experiences have taught you. Also carry a canoe around a little while. It is not quite the same as backpacking. You might adjust how far you can go.
The BWCA also has some great hiking trails, an option.
If you are not from the area a drive up the North Shore of Lake Superior is worth the time. Otherwise there are no bad places in the BWCA other than a couple of the entry lakes that really get heavy use. Decide what area you want to head into and pick any of the outfitters listed under the Outfitters heading above. I have been tripping since the late 70's and never had a bad outfitter experience in the BWCA. A few chats with them and they will get you a few great ideas. Then use the search function, also above, and type in those lakes. You will find reports of folks who have traveled in that area, often with photos. Post some of your thoughts here for more feedback.
Follow up with some posts about what you did decide and how it went. We love feedback.

Sawbill Outfitters is a top-notch operation. Their website has a couple 3-4 day routes that would suit your family, particularly the the Cherokee and Lady Chain routes. There is also a very nice forest service campground right next to the outfitters, where you could stay the night before your trip.

My wife and I did a 4-day, 3-night trip out of Snowbank Lake east of Ely. We had virtually flat water so paddling Snowbank from the landing to the northeast corner was no big deal. We paddled and portaged through the smaller lakes and got into Ima, then circled back through Ahsub, Disapointment and back to the landing on Snowbank. A very nice, relatively relaxing and doable trip. Only one semi-hard portage around Haven Lake. We really enjoyed this route, just remember to grab a campsite early.

Here is our trip report.

Welcome to the board, and happy planning!

If you are asking for this summer, many of my favorite entry points could be reserved already.

Here is one suggestion on seeing the quintessential experience in 4 days - most take longer

Take a tow in from Fall lake - it probably has not ran out. I know of one great outfitter - Packsack - that could outfit you and help tow you up to the end of Basswood allowing this whole thing to be doable for a family in 4 days.

You have one long, long (but flat) portage to get into the Crooked Lake system with pictographs, then head down the Horse River and eventually out Mudro. some of the best falls, campsites, historic spots along this route.

Check out Seagull Outfitters.

I take short trips every Memorial Day. We have stayed on Red Rock Lake, Alpine Lake, and Seagull Lake. All three of those lakes are very easy to get to in a few hours and then you can basecamp for 3-4 days and come home.

We usually paddle directly from the Seagull dock and paddle back at the end of the trip. But you can also take a tow to Red Rock. The tow boat ride is quite an adventure all by itself. The kids might like that.