Materials & Prep
Gather one ten-frame and a small pile of two-colour counters for each pair. Place counters where partners can share them. No other special setup is needed.
Gather and model
Ask“Can five counters be made in a way that is not four red and one yellow?” Have children show thumbs-up or thumbs-down for their prediction, then turn and tell a partner why. Do not correct the predictions yet.
ModelPlace five counters on a ten-frame, using four red counters and one yellow counter. Think aloud: “I count five counters altogether. Four are red and one is yellow, so this is one way to make five: 4 + 1 = 5. The five spaces are still filled even when I move the color boundary.”
ConfrontRearrange the same five counters as three red and two yellow. Say, “I did not add or take away a counter. I only changed the groups. Now I have another way: 3 + 2 = 5.” Ask children to explain how they know the total stayed five. Name the common mistake: “Five is not only four and one. The same total can have different parts.”
Show me: Have children use their fingers or counters to show the parts in 2 + 3 = 5. Ask, “What are the two parts? What is the whole?”
Build and share
TransitionPartners take one ten-frame and two colours of counters. The teacher calls a target number from 5 through 10. Partners build that number, count the whole, split it into two colour groups, and then rebuild it with a different split.
Partner talk: Partner A builds the first way. Partner B counts all the counters and says, “I see __ and __. Together they make __.” Partners switch jobs for the second way. Accept pointing, showing counters, or saying the numbers as a response.
ScaffoldKeep a five-counter model visible for children who need an entry point. Offer the spoken frame, “I made __ with __ and __. I know it is __ because I counted all the counters.” Model one turn again at the child’s frame if needed, then let the child change one counter’s colour to find a new split.
Check for understandingPause after the first round. Ask selected pairs to hold up both arrangements for the same target. Ask, “Did the whole change, or did only the parts change? How can you prove it?” Look for children counting the total and naming two different parts, not merely changing the position of the counters.
Worked exampleFor a target of six, show five red counters and one yellow counter, then four red counters and two yellow counters. Say, “Both arrangements have six counters altogether: 5 + 1 = 6 and 4 + 2 = 6.”
ExtensionChildren who are ready choose eight, nine, or ten and find three different splits. For eight, one possible set is 5 + 3 = 8, 4 + 4 = 8, and 6 + 2 = 8. They explain how each pair has the same whole.
Come back together
ShareInvite two pairs to show different ways they made the same target. The class counts each arrangement aloud and identifies the two parts and the whole.
ChallengeGive each child or pair a target of five, six, or seven. They must build two different ways, place both on the ten-frame one at a time, and orally explain, “These are different parts, but the whole is still __.”
Close: Ask, “What does it mean to decompose a number? How can you show that five is more than 4 + 1?” Listen for an answer that names breaking a whole into different parts and gives another valid arrangement, such as 3 + 2 = 5.