Cuthbert Harris wrote many teaching pieces for piano, and this selection provides a standard example of late nineteenth-century educational literature. It focuses on maintaining a singing tone.
Ensure the student demonstrates a clear distinction between the melody and the accompanimental chords.
Comparable difficulty and character — good candidates for what to learn next.
At twilight is rated Henle level 2 of 9 — beginner repertoire, roughly ABRSM grades 2–3. In the RCM system it corresponds to about level 3.
You should be comfortable at Henle level 2 — meaning you can already play level 1–2 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of At twilight lasts about 2 minutes.
At twilight is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Beside Still Waters by Bernard Hamblen, 'Adeste Fideles' with Variations by W.E. Tipper, Autunno (preludio) by Tatiana Stankovych — see the full similar-pieces list on this page.