Building with longer rods

A challenging activity focusing on finding all possible ways of stacking rods.
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

Problem



This activity has been particularly created for the highest attainers.

When you have completed Building with Rods then go further with this challenge of using rods that are $3$ units long.

Same rules as before - so just to remind you; here are two solutions that fit the rule. 

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Building with longer rods

Here are two that don't fit the rule as the small cubes have to be lined up squarely, with no overlapping. 

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Building with longer rods

The challenge is to find all the possible ways of stacking the rods, keeping the blue rod on the bottom, the red rod in the middle and the green rod on top. 

What do you think will happen if you try the same activity with rods that are $4$ long?

What do you think will happen if the rods are $5$ long?