HANDWASHING
five steps, and the 20 seconds that actually matter
LOGIC GATES
Seven digital-logic symbols — and how to build six of them from a single element, NAND
THE 9 MAJOR FOOD ALLERGENS
the foods US law singles out by name, and the two ways a label is allowed to say so
THE BRAILLE ALPHABET
63 characters of the cell in seven lines — 26 letters, the digits, the punctuation and 8 prefixes
IRREGULAR VERBS
the 100 you meet most: base · past · past participle — grouped by the four patterns, not shuffled alphabetically
LANGUAGE FAMILIES
who is related to whom — on the numerals three and two in twenty-seven languages
LETTER TEAMS
40 letter combinations and the sounds they spell, in IPA, with one example word each
SIGHT WORDS
all 220 Dolch service words in five grade groups, Pre-K through third — with the top of the Fry frequency list up front
DIVISIBILITY TESTS
what to read in a written number instead of dividing it: the tail, the digit sum and composite divisors
LEAP YEARS
one rule, a cycle of four hundred years and the ninety-seven extra days in it
PASCAL’S TRIANGLE
the first thirteen rows, the sum of each row and the pattern of the odd numbers
ROMAN NUMERALS
seven symbols · ones, tens, hundreds · years