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Building bricks

For the grown-up beside a child who loves building bricks.

The child's own door is Building bricks on Spark & Anvil.

There is no Whetstone tool or course for building bricks yet, so this page is the sideline card and your child's ladder.

The sideline card

Three numbers to notice

  1. Three thin plates stack to the height of one brick.
  2. Five plates stand as tall as two studs are wide, so a piece turned on its side still lines up with the rest.
  3. Six 2-by-4 bricks of one colour fit together in 915,103,765 different ways.

On the way home, ask: “Which piece did you need most today, and why?”

Ask because you are curious, and let any answer stand. Print this page for a half-page card.

Numbers checked against: Søren Eilers: the LEGO counting problem; Durhuus and Eilers, On the entropy of LEGO; worked by hand, lines 1 and 2 (a plate 3.2 mm, a brick 9.6 mm, studs 8 mm apart: 3 × 3.2 = 9.6; 5 × 3.2 = 16 = 2 × 8)

Your child's ladder · on Spark & Anvil

The same idea at every age

  1. Ages 3–5Tall or Long
  2. Ages 6–8Count the Studs
  3. Ages 9–14Two Bricks, Twenty-Four Ways
  4. Ages 15–18How Fast Bricks Grow

Your child will meet this idea again at every age. The sideline card is the part for you.