Showing posts with label story problems. Show all posts
Showing posts with label story problems. Show all posts

Tuesday, December 1, 2009

On Family Size

It's important to connect numbers with real-life situations. Which is why I had 4th graders tell "stories" about the multiplication expression 4 x 6 as a warmup for a lesson this week. By "stories," I hasten to say, I don't mean great literary efforts, with foreshadowing and metaphor and plot twists and poetic license and all those great things. No, I mean simple situations like these:

"There were 4 glasses and each glass had 6 ice cubes in it."

"There were 4 people and each one ate 6 hot dogs."

"I saw 4 flowers. Each flower had 6 petals."

You'll note that in each case the 4 [the first number in the expression] represents the number of groups, and the 6 [the second number in the expression] represents the number in each group. Of course, 4 x 6 is equal to 6 x 4, which all the children I was working with that day knew perfectly well; but it's useful to think of the first and second numbers each playing a slightly different role in the expression.

And we were progressing swimmingly until one boy said, "There were 4 families and each family had 6..." Then his voice trailed off, and he thought, and then he said, "I mean, there were SIX families, and each family had 4 people in it."

Real-life situations indeed. No prizes for guessing how many people there were in his family!

Monday, June 8, 2009

Fifteen Tires Were on Top of a Hill...

Robbie recently had her kindergarteners write story problems. They thought of a situation that involved plus ("joining") or minus ("taking away"), then wrote the story, wrote the number sentence for the problem, and finally made a box with clay figures and other decorations showing the problem. Today, they demonstrated their work for the class.

There were 15 tires on top of a hill...



Then five of them rolled down the hill....



How many were left at the top of the hill?

Hope you got 15 - 5 = 10!

Sally the snake sees 5 dragonflies. 2 fly away. How many are left?



Did everybody get 3? If not, ask your nearest kindergartener for help.

Other problems involved bats or butterflies flying off into the great big world, horses venturing out from the safety of barns, and wolves scaring away some (but not all) of a group of farm animals. I'm no psychologist, but it's pretty easy to tell that kindergarten is drawing to a close!