This is what the ABRSM lay down as guidelines; any song meeting the guidelines will do:

UNACCOMPANIED TRADITIONAL SONG (folk song)
In all grades, candidates are required to perform an unaccompanied traditional (folk) song
of their own choice, from memory. A traditional song is defined as a folk song originating
among the people of a region and forming part of their culture. Folk songs are essentially
colloquial and have no traceable composer, and they cover a broad range of topics, such as: the
natural world and the cycle of life; love and romance; work and relaxation; historical events;
and situations of hardship, suffering, inequality and rebellion.
The following genres are not suitable: hymns, carols, chants, plainsong; nursery rhymes;
national anthems; stylized folk song arrangements (i.e. that would rely on their piano
accompaniment for the full musical effect to be achieved)
The unaccompanied traditional song may be sung in any language. An English translation
orshortsummary should be provided for the examiner when words other than English are used.
The song may be sung in any key comfortable for the candidate, and, if required, the first note
or key-chord may be played on the piano to establish the pitch. The candidate's unaccompanied
traditional song must not be the same song as any chosen from the lists of accompanied songs
in the same exam.
Candidates must ensure that the unaccompanied traditional song fulfils the following timings:
minimum maximum
Grades 1–4 1 minute 2 minutes
Grades 5–8 1 minute 3 minutes
Possible sources
There are no 'set' songs for this part of the exam. Candidates are free to perform any song
from any source or publication at any grade (provided the guidelines above are followed).
The many available collections of traditional/folk songs include the following:
- Sing Together (available in melody-only and accompanied editions: OUP)
- Best of Folk Songs: 40 British, Irish and American Songs (available in melody-only and
accompanied editions: Schott ED 12881 or 12880)
- TheABRSM Songbook, Books 1–5 (ABRSM) (each album containstwelve unaccompanied
traditional songs)
- Folk Voiceworks: 30 Traditional Songs (OUP)
- The Library of Folk Songs (Amsco AM 961521)
- ASelection of Collected Folk Songs, Vols 1 & 2, arr. Sharp & Vaughan Williams (Novello
NOV190038 or NOV190040)
- Folk Songs of England, Ireland, Scotland and Wales (Alfred VF1880)
- The New Scottish Song Book (Hardie Press

LFF