In Robert Frost's "Desert Places," the rhyme scheme is A A B A. A rhyme scheme is what the author uses to create a pattern of rhyme. In this case, Frost sticks to that pattern throughout the poem. The rhyme occurs with the last word of the line, so to chart the rhyme scheme, one must look to the sound of the last word in each line of the stanza. In this poem the first two lines and the last line in each four-line stanza rhyme with each other. For example, in the first stanza, the last word of three of the four lines rhyme, with the words "fast," "past" and "last" (the sound represented by the letter "A"). The last word of the third line is "snow," and it does not rhyme with the others (so its sound has been labeled with a "B").
The meter of a poem is defined as:
...a rhythm of accented and unaccented syllables which are organized into patterns...
The meter of the poem is iambic pentameter. This means that there are ten syllables per line with the stress beginning on the second syllable of the line, and repeating then on every other syllable until the end of the line is reached.
For example, look at the line below:
The woods around it have it—it is theirs.
The stress begins on the word "woods" and the pattern continues, resting lastly on the word "theirs." In the following line, the words are displayed to show where the emphasis (or stress) rests. Any words with more than one syllable are generally separated with dashes (and there is only one of these in the line below); the stressed syllable (or word) is bolded.
The woods a-round it have it—it is theirs...
The form used in the poem is called "closed form" which is...
A type of form or structure in poetry characterized by regularity and consistency in such elements as rhyme, line length, and metrical pattern [or meter].
The form is "closed" because Frost has consistently used the same rhyme scheme throughout the poem. The meter is the same because Frost uses iambic pentameter continuously in each line, and in sticking to this pattern of beats (meter), the length of each line is the same.