The Math Ideas in a Handful of Blackberries

Last winter, Janelle, Jonylah (Jo-NYE-lah) and I spent a few early morning minutes marveling at three deer who had jumped the fence into our backyard. But once one started munching on our blackberry bush, it was time for them to go!

This surfaced a memory of a math moment from last summer when that same bush had started to produce fruit—to the excitement of my 4- and 2-year-olds (and let’s be honest, me too)! Early in the season, I picked off the first berries and brought them inside.

I showed Janelle, who was 4 years old at the time. “I picked these 8 blackberries from the garden. You need to share them equally with your sister. How many should you each get?”

Her reply? “Well, I’m four, so I get four, and Jonylah is two, so she gets two.” 🤣

Who am I to argue with that logic? I did, however, ask, “Then how many would be left?”

Janelle did some counting on her fingers and reported, “Four.”

Obviously, this was incorrect, but I decided not to pursue it further at the moment. Instead, they enjoyed their blackberries, and we attempted to keep sticky, juicy fingers from staining everything in sight.

A Second Look

Later on, I gave Janelle eight counters and asked her again, “How many would you and your sister each get if you have to share equally?”

First, she said four and made two groups of four.

This was a key moment—it would have been easy to stop here and move on with our day. But the math teacher in me wanted to be sure she truly understood. So, our conversation continued.

“How do you know?” I asked.

“No wait, I would get three, and my sister would get three.” She put the other two aside.

I pointed at the two she set aside. “Who would get those?”

“You and Daddy.”

“What if only you and your sister could have them? Is there enough for you each to have more?”

“Yes, because there are two. We could each have one more. So we each get four!”

“Have you used them all up?”

“Yes, because there are 8.”

Post-Game Analysis

Building Trust in Reasoning

Given Janelle’s correct answer of 4, it would have been easy to assume she “got it.” But through my Master’s in Teaching Mathematics coursework, I eventually learned to avoid equating correctness with understanding. Here’s why:

1. Our assumption may be wrong, leading to missed learning opportunities.
2. When we only ask about thinking or reasoning when an answer is incorrect, kids quickly internalize the questioning as a cue that they are wrong. Instead, making it a habit to ask about their thinking—whether the answer is right or wrong—builds a child’s trust in their own reasoning.

In the end, Janelle still came back to the answer of four. But our conversation shed light on her thinking, and she convinced not only me but, more importantly, herself.

Your Turn!

It took me years to learn that simply accepting right answers as proof of understanding wasn’t enough. You can start using this insight today by making it a habit to ask about your child’s thinking—whether their answer is right or wrong!

Have you noticed moments like this in your child’s play or problem-solving? Start keeping an eye out!

Looking for more specific, easy preschool math activities? Check out my free resource, 3 Powerful On-the-Go Early Math Activities!