It may be a little out of your distance but Lac La Biche lake continues to be a good producer and access is usually not an issue. I would also suggest Beaver but Beaver can have access issues.

ps.
feel like I'm missing something when it comes to laclabiche tho.
was there last year. went to where all the reports said good perch. spent a good half a day. landed lots but best was maybe 6" and the average was 3-4". nothing worth the effort. did c'n'r a nice fat 4lb class walleye tho!!!!

I guess labiche can do that to you often,, just give up the little buggers, but if you move around the nice ones can be found. Not that I am an expert on the lake by any means but my son fishes it often and seems to do quite well, no 2lber's or anything but he does consistently bring home nice eating fish. Try area's like Golden Sands, or Poplar Point for Pike and Perch. Just south of the Mission out on the flats for some insane Burbot fishing.

I hope you find a spot for your son to try,, most of the lakes I know of are off the grid so to speak access by ski doo or quad only.. Sure he to try a few this season.