Short /ɪ/ almost everywhere, long /aɪ/ before silent e and in a handful of very common families that look closed but are not.
Letter sounds
i LETTER_I_01
Useful pattern · Medium reliability · Very common · Early · Reading
/ɪ/ short i: sit, pig, win
/aɪ/ long i: bike, find, mild
/ə/ schwa: pencil, family, possible
/iː/ long e sound: ski, machine, pizza
Where Wiggler teaches it: Skill 1: First Sounds & Blending · Skill 6: Magic e · Skill 11: Advanced Patterns & Silent Letters · Skill 12: Multisyllable Decoding
Child explanation
I usually says /ɪ/ like in sit. With an e on the end it says its name: bike. And in find and child it says its name too, even though it looks like it should be short.
The rule
Short /ɪ/ in a closed syllable. Long /aɪ/ with a silent e, before gh, and in the -ind, -ild and -igh families. Schwa when unstressed.
What is really going on
Short i is the default and is highly consistent in closed syllables. The long value appears predictably with silent e, with the igh trigraph, and in the historically conditioned -ild and -ind sets, where the vowel lengthened before a consonant cluster in Middle English. In French-derived words i can also represent /iː/ — machine, marine, police, ski.
Position in the word
Middle of a word — Short in a closed syllable. For example: sit, big, milk, print.
Before a consonant — Long before -nd and -ld in the established families. For example: find, kind, mind, wild, child.
End of a word — Very rare at the end of an English word — y does that job instead. For example: ski, taxi, mini.
Unstressed syllable — Schwa. For example: pencil, family, April.
Made-up words that follow the rule. A child who reads these has the pattern rather than the vocabulary.
blig, trind, shipe, flight
Exceptions
i as /iː/: machine, police, marine, ski, pizza, unique. French and Italian loanwords keep the source language's value for i.
give and live: give, live, olive. Final e here is preventing a word-final v, not marking a long vowel.
Contrast pairs
win versus wine — Closed versus silent e.
fin versus find — Closed versus the -ind family.
bit versus bird — Closed versus r-controlled.
Common reading mistakes
find: a child reads /fɪnd/, where the word is /faɪnd/. Short i applied to an -ind family word.
give: a child reads /gaɪv/, where the word is /gɪv/. Magic e over-applied where the e is blocking a final v.
Teacher note
Short i and short e are the pair children confuse most. Work the contrast by ear — pin/pen, bit/bet, lid/led — before doing it on paper. Teach find, kind, mind, child and wild as a family with a chant rather than as exceptions, at the same point you teach -old and -ost; they are among the most frequent words that break the closed-syllable rule, and naming them as a set removes almost all of the damage.