Almost everyone knows the first stanza of "The Star" as a song, which makes it easy to forget that Ann Taylor's poem runs to five stanzas, and that the later ones are where the thinking happens. What begins as a child's delighted question becomes a quiet argument that the star matters for two reasons at once: it is wonderful, and it is useful.
The opening stanza is pure wonder. The speaker asks "what you are" and can only answer with a comparison: "Like a diamond in the sky." A diamond is the sort of guess a young mind would make, since it is bright, precious and out of reach. Then the poem changes direction. The sun arrives, "blazing" and personified as "he", and the star takes over its work: it shows its "little light" only "when the blazing sun is gone." The contrast between "blazing" and "little" matters, because the star never competes with the sun. It steps in when the sun has left.
By the third stanza the diamond has become a spark. The "trav'ller in the dark" thanks the star "for your tiny spark," because "he could not see which way to go, / If you did not twinkle so." That shift of imagery is the poem's real turn. A diamond is something to look at, while a spark does a job. The star moves from treasure to tool without losing any of its charm.
Stanza four brings the star indoors. It "often thro' my curtains peep[s]" and "never shut[s] your eye / Till the sun is in the sky." Now the star is a watcher, almost a companion for someone lying awake. Judging by the bedroom setting and the plain, direct address, the speaker is probably a child, though the poem never says so. Even the verb in "In the dark blue sky you keep" can mean simply "stay", but beside that sleepless eye it also suggests keeping watch. So the star is seen three ways, as diamond, spark and eye, and each one stands for a different feeling: admiration, gratitude, comfort.
The form suits this simplicity. Each line has seven syllables in a trochaic rhythm, with the stress first: "TWIN-kle, TWIN-kle, LIT-tle STAR." The final unstressed syllable is dropped, so every line ends on a beat and the rhymes land firmly. The rhymes come in couplets (star/are, high/sky, gone/upon, light/night) and use short, everyday words, which makes the poem easy to memorise and easy to sing. The steady beat even feels a little like a light blinking on and off. To keep that beat, the poem clips and bends its language. "Trav'ller," "thro'" and "tho'" are trimmed to the right length, and "When he nothing shines upon" twists normal word order so that "upon" can rhyme with "gone."
The ending is carefully built. The last stanza recycles earlier material: "bright and tiny spark" and "trav'ller in the dark" repeat stanza three with the order reversed, and the final couplet returns to the "are/star" rhyme of the opening. The one important change comes in a single line. "How I wonder what you are" becomes "Tho' I know not what you are." The question is never answered, only accepted. The speaker has been given light and company by something that remains a mystery, and the poem treats that as enough. The final line, "Twinkle, twinkle, little star," is then the same words as the first, but now they sound like thanks rather than a question.
This is why the poem deserves more attention than its nursery reputation suggests. It teaches, without a trace of lecturing, that you can value something without fully understanding it, and that awe and practical gratitude can go together. Its vocabulary stays within a small child's reach, so the idea arrives through the rhythm and the repetition. Many readers meet this poem long before they know what a poem is, and its plain, steady lines are a large part of why it stays with them.