I walk past the neighbor’s garden and feel habitual comfort at the sight of bees clustering in the Russian sage. Bees are good. Bees are pollinators. Why is that good? Because I want my apple tree to bear fruit. Is it good to be a bee? What is it like? I have no idea. I once had a dream about seeing the throne of God surrounded by angels, but the angels were butterflies and bees. A horticultural God surrounded by his pollinators.
Concerned people in the neighborhood have put up Facebook posts about the evils of black swallow-wort. It is an invasive vine that interferes with monarch butterfly reproduction, I read. If your yard is full of it, people concerned about invasive species hang a special sign on your fence. I see it everywhere now. They will never get rid of it. I wonder how they chose black swallow-wort of all the available moral crusades.
Sometimes the lampposts in my neighborhood have signs obviously made by a precocious first-grader. In belabored magic marker they spell out the importance of preventing hive collapse (illustrated). “IF THE BEEZ DY THER WILL BE NO FLORS”
I feel affection toward lady-bugs because they are good. Why are they good? Because they eat aphids. Why are aphids bad? Because they eat roses. Does the rose care? No, but the gardener does.
We went to the beach, and Lily brought her croquet mallet. “If I see any bugs I’m going to swing this croquet mallet right around, because you know how I freak out if there are bugs.” But not ladybugs. “I’m not going to get the ladybugs because they’re good for life.” Where did she learn this? I don’t know. Whose life are they good for? Not the aphids’.
I teach the kids the rule I decided on before they were born: bugs may be killed inside but not outside the house. “Inside is our home. Outside is their home,” I tell them. They are not persuaded. An ant is still an ant to them. I can’t find the hole in their reasoning.
Anna talks about killing birds and rabbits. I’m not sure why I find this so much more disturbing than killing ants. I let her chase them, knowing she’ll never catch one.
The whole sky 
I think kids (and well-adjusted adults) develop a good sense of the difference between ants and rabbits and people’s “agency” over time… the concern would be if they don’t develop it, or seem to have wanton disregard for animals. I’ll confess — when I was a kid, my dad had this powerful magnifying glass, which I discovered could burn holes in dry leaves. I found that it could also do a sizzling number on ants walking across our patio. Looking back, if I was my mom, and I saw my child engaged in that activity more than a couple times (or looking forward to it!) I’d step in and say something.
I liked your observation about ladybugs!
I’m in my 60s now and continue to grow more tolerant of outside bugs, but not black widows, and I don’t really like spiders hanging around our outdoor lights, which they make a mess of. Emerald ash borers are on my s*-list along with wooly adelgids (hemlocks) and other insects that do more than cosmetic damage. If one granted all insects equal “agency”, one would be bothered by the inconsistency in how one regards ladybugs and ash borers. However — we (at least in USA) don’t stop and mourn and have a funeral when we accidentally step on an ant, or a moth hits our windshield. We are sorry when a bird flies in the window and dies, but we (mostly?) don’t mourn a long time or have a burial rite either. Our pets, we do mourn because they’re around us a lot and we ascribe to them a personality — sometimes more than their actions merit, but anyway. My point is that kids observe adult behaviors around animals, and that is probably enough in most cases, without explicit lessons — assuming the adult is well-adjusted.