If you have children or regularly spend time with them, you’ve likely realized that kids teach us adults as much if not more than we teach them. That was my experience as a mother and now that I’m a grandmother, I can tell you class is still in session. My two granddaughters, ages 3 and 4 ½, recently stayed with my husband and me for two glorious weeks, during which time we received an education that went far beyond learning the names of all the characters in “Bluey.”

Food was the main theme for this unit and the first lesson involved learning the particulars of produce, specifically the difference between strawberries and blueberries. Actually, I already knew the difference between them, the colors were a big clue, but until my granddaughters schooled me—at full volume, mind you—I’d been unaware that there were certain days assigned to each fruit. Believe me, I will never again commit the egregious error of attempting to serve blueberries on what is (ahem) so clearly “a strawberry day.”

Along the same lines, there is a strict protocol for combining donuts, icing, and sprinkles. It’s not as simple a process as you might imagine. First there is the icing color to consider, pink or white. Pink is the perennial favorite, but if it’s late in the day when Dunkin’ Donuts has zero pink-iced donuts left and an exhausted Nonna (gently) puts her foot down, white may be deemed an acceptable alternative—provided critical guidelines regarding the usage of sprinkles are followed. Let me be clear here. Whereas putting sprinkles on pink icing is absolutely de rigueur, putting sprinkles on white icing is a high crime, apparently tantamount to wearing white—clothes, that is, not icing—after Labor Day. Pink: sprinkles; white: no sprinkles, got it? Confuse the two and donuts of every variety, despite having been bought and paid for, are immediately and dramatically rendered inedible.

But the most eye-opening development for me was discovering that the principle “form follows function” has a lesser-known second half, “as flavor follows form,” which when violated can have disastrous consequences. I offer the following examples:

• While corn kernels still on the cob are greeted with delight by young children, once those very same kernels are cut from the cob to facilitate more complete preschooler consumption, they are transformed into rancid particles of toxicity from which anyone wearing size 3-4T clothing must recoil in shrieking horror.

• Be aware that if a small child insists on opening a Z-bar herself, she will likely pull it into two pieces when removing it from the sticky wrapper, at which point it will no longer be an acceptable snack. Even if, due to the moist texture of said bar, Nonna is able to smoosh the pieces back together, it is NOT the same bar as, quite obviously, all the flavor escaped in the pulling-apart process. The only option to stem the ensuing meltdown is to open a new bar at once and discard the deformed, flavorless reject (usually directly into Nonna’s mouth, which explains the five pounds she gained during the grands’ visit).

• As far as the shape of frozen waffles goes, understand this, round waffles do not taste the same as square waffles. Don’t be fooled by the advertising on the box, which purports both shapes to be the exact same flavor. Buy a box of square and a box of round because whichever shape preference children express at the store will automatically reverse once you arrive home, and without the alternate shape on hand, believe me, breakfast will be no picnic.

• Speaking of shapes, this point about boxed macaroni and cheese is so elementary it should go without saying, but I’ll say it here for the new grandparents in the back: macaroni shapes are not interchangeable. Only a total grandparenting rookie would imagine that, despite being made of the exact same ingredients and smothered in the exact same radioactive orange goo, one noodle shape could be substituted for another without a change in flavor. Do not attempt to spring on children any macaroni shape other than the one they are accustomed to eating. It will not go well.

If you still question the validity of my findings, I leave you with this final cautionary tale which should erase all doubts. My granddaughter Nora’s default food setting when all other meal offerings have fallen short of her standards is a peanut butter-and-jelly sandwich, cut into triangles—meticulously cut, equilateral triangles. While she’s willing to give a little on the flavor of jelly—grape or strawberry—the precision of the cut is non-negotiable. Once when my knife slipped, I tried to sneak an isosceles by her, with disastrous consequences. After that I kept a compass and protractor handy in my kitchen utensil drawer. (The price of a desktop laser cutter forced me keep it old school.)

Anyway, one day when I was running a little late getting home from teaching my morning class, my husband took it upon himself to fix the girls’ lunch. I walked in the door to utter pandemonium, with Nora wailing, “I want triangles, Papi,” my husband Jorge wailing, “These are triangles, Norita” in response, and my other granddaughter Tess wailing, just on general principle.

Nora and Jorge both lunged at me the minute I entered the kitchen, pleading their separate cases. I took one look at the highly questionable shapes my husband was trying to pass off as equilateral triangles and immediately sided with Nora.

 “You call these equilateral?” I squawked at my husband. “Good grief, Jorge, you’re a civil engineer and you don’t know basic geometry? Why didn’t you use the protractor and compass I keep in the drawer?”

“I thought I could eyeball it,” he responded sheepishly.

“Oh, you thought you could eyeball it, huh? Let me tell you something, maybe you can eyeball the angle of a highway or bridge, but not sandwich sections. Didn’t they teach you anything in engineering school?” I asked rhetorically, shaking my head in disbelief.

So, I remade Nora’s PB&J according to her specs and even made an extra one for Jorge and me to share. Peace and quiet once again reigned as all four of us settled down to watch an episode of “Bluey.”

“You know,” remarked Jorge as he took another bite of a triangle, “I think Nora’s right. The equilateral sides do enhance the flavor of the sandwich.”

And there you have it, my friends, definitive proof that flavor follows form. Ignore this principle at your own risk. Oh, and happy grandparenting!