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Collecting cards

For the grown-up beside a child who loves collecting cards.

The child's own door is Collecting cards on Spark & Anvil.

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

The sideline card

Three numbers to notice

  1. The number at the bottom of a card, like 45/198: card 45 of a set of 198.
  2. A number bigger than the total, like 224/198: an extra card printed beyond the main set.
  3. Finishing a set by chance slows down at the end: if every card is equally likely, collecting all six of a six-card set takes about 15 picks on average, and the last card takes the longest.

On the way home, ask: “Which card would you trade for, and what would you give?”

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

Numbers checked against: Pokémon Trading Card Game Rules (the collector card number); worked by hand, line 3 (6 × (1 + ½ + ⅓ + ¼ + ⅕ + ⅙) ≈ 14.7)

Your child's ladder · on Spark & Anvil

The same idea at every age

  1. Ages 3–5Which Cards Are Missing?
  2. Ages 6–8Collect All Six
  3. Ages 9–14Not made yet
  4. Ages 15–18The Last Card Problem

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