The blue ribbon reaches further across the table. But look at where it starts.
Place a shorter blue ribbon and a longer yellow ribbon flat on the table, with the blue one starting further forward. Arrange them so the blue ribbon finishes beyond the yellow one. Then ask, “Which looks longer? How could we check?”
Your child might choose the ribbon that sticks out furthest. That answer gives you somewhere useful to begin. There’s no need to correct it straight away. Let the ribbons do the explaining.
Give both ribbons the same start
Put a book on the table and use its straight edge as a starting line. Lay the ribbons beside each other so they’re flat, straight and pointing in the same direction. Don’t pull them tight. Invite your child to bring one end of each ribbon to the book’s edge.
Now both ribbons have the same starting place. This makes it possible to compare their lengths directly by looking at where their other ends finish. The Mathematics Hub’s Foundation guidance on comparing measurement describes bringing objects together and aligning their ends as a useful way to compare length.
If attention wanders to the colours or widths, gently bring it back: “We’re checking how long each ribbon is from one end to the other.” A ruler isn’t needed for this comparison.
Keep the ribbons straight for now. A curved or wiggly ribbon can look shorter from start to finish even though the ribbon itself hasn’t become shorter.
Look at the other ends
Once the starting ends match, the yellow ribbon extends beyond the blue one. You might say, “The yellow ribbon is longer than the blue ribbon,” followed by, “The blue ribbon is shorter than the yellow ribbon.”
Ask, “What do these ends show us?” Your child doesn’t need to produce a polished sentence. They can point to the extra part of the yellow ribbon, trace a finger along each piece or adjust the ribbons to show you.
The words longer, shorter and same length are useful here because they describe the relationship between two objects. They make more sense when they’re attached to something the child can move and see.
Slide it, then check again
Leave both ribbons straight and unstretched, then slide the shorter blue ribbon forward until its far end passes the end of the yellow ribbon.
“Did the blue ribbon get longer, or did it move?”
Give your child a moment to look. Then ask, “Can you show me how we could check?” They can slide the blue ribbon back until both starting ends meet the book again. The yellow ribbon will still extend further.
The blue ribbon is the same length as it was before; only its position changed. That isn’t the same as saying the two ribbons are the same length. This blue-and-yellow pair remains unequal, however you slide it around the table.
If your child is unsure, simply move the ribbon back and try the comparison again. Another look is often more useful than a longer explanation.
What would the same length look like?
If your child wants another turn, bring out two separately prepared ribbons of equal length. Mix up their starting positions first, then line up one end of each against the book.
This time, both the starting ends and finishing ends match. You can say, “These two ribbons are the same length.” Let your child swap, slide and realign them to check that moving either ribbon hasn’t changed it.
A small Foundation maths conversation
This simple arrangement supports the length part of Foundation Mathematics content description AC9MFM01, which includes directly comparing length and communicating the reasoning behind a comparison. A child can communicate that reasoning with words, pointing or a demonstration.
One response doesn’t need to become a test. Notice whether your child checks the starting ends as well as the finishing ends, and explore again if the placement is still distracting.
Then hand the arrangement back: “Your turn—put the ribbons down and show me how you’d check.” A demonstration, a few words or another look together is a useful place to finish. The simple habit to keep is this: match the starting ends before comparing the finishing ends.