You don't say how old your boys are--whether they are likely to outgrow their gear or not. Adult-sized bags can be colder for kids just as too-large bags can be colder for adults. But I haven't found any kid-sized bags that were significantly cheaper or lighter than adult bags. When I have the time, I'm planning MYOG quilts.
My two girl (8 and 15) sleep comfortably on closed cell foam pads, even if I wouldn't. Z-rest or Ridgerest are nice, although I just use the inexpensive ones from big box stores, ~$10, which I cut down to 3/4 size. Weight is 5-7 oz.
My oldest girl does great with hiking poles, my youngest not so much. She'll use one for a quarter mile and then starts dragging it. My poles are adjustable, so I just loan her one of mine for the two or three times during a hike she wants to use it.
I mostly use a MYOG alcohol stove. Since the stove is cheap (free) and quick to make, I made another that my oldest daughter carries as well. A bit redundant, but the weight isn't significant, we boil water twice as fast with 2 stoves, and she learns how to use the gear. She carries all her own stuff (she's 5' and 100#) except I carry most of the tent; her total pack weight starting a 3 day was ~ 16#. My youngest (4' and 60#) carries her clothes, sleeping bag, and pad, plus some water and snacks--I keep her total pack weight down to 10% body weight or less. If she's dragging a bit, I try to take weight from her unobtrusively (e.g., when she takes off her jacket, I'll put it in my pack rather than hers).