Once in a Blue Moon - A Homeschool Conversation

A typical homeschool conversation:

As we opened Christmas cards, the kids asked who one of the senders was. I explained that it was a parent of a old Girl Scout whom I hadn’t seen in many moons.

“Many moons. Why do people say that?” DS asked.

“It just means I haven’t seen her in a while,” I responded thinking that would suffice.

“Wouldn’t many moons just mean a couple of days?” He continued.

“No, they mean full moons, so they mean months.” Of course, then I had to add, “except for those blue moons.”

“Blue Moons. What is a blue moon?”

“The second blue moon in a month.”

DD piped in, “How often does that happen?”

“Daddy?” I had used up my knowledge of the moon cycles. He plugged “Blue Moon” into his laptop and came up with www.obliquity.com/astro/bluemoon.html“The average interval between Full Moons is about 29.5 days, whilst the length of an average month is roughly 30.5 days. This makes it very unlikely that any given month will contain two Full Moons, though it does sometimes happen.
On average, there will be 41 months that have two Full Moons in every century, so you could say that once in a Blue Moon actually means once every two-and-a-half years.” He read from the website.

Then we digressed into when the next blue moon was, why they are called blue, and other great astrological facts.

Then dear son brought us back down to his crazy thoughts, “Well, when will four blue moons happen in the same month?”

I thought for sure he had missed the whole concept of what we were just saying. I started waxing on about 29.5 days in a cycle, you would need more than 30 days in a month . . .DD added that we’d need more than one moon and have to be like on Jupiter. But no DS, explained God could cause a miracle and align the moon cycles to his desire. Ok, who can argue with that? I just rolled my eyes. . . “I guess you’re right!”

Now for those states that require reporting - where do you put such conversations? Should homeschoolers try to write all of their digressions down? This was not on our science plan for the day, but certainly is a valid lesson.