Louis Tocaben's 'Boat Song' is a characteristic pedagogical work intended to introduce the barcarolle style to young learners. It utilizes a recurring rhythmic motif to simulate the repetitive motion of rowing.
Pay close attention to the rhythmic consistency of the 6/8 meter to avoid rushing the triplet pulses.
Comparable difficulty and character — good candidates for what to learn next.
Boat Song is rated Henle level 2 of 9 — beginner repertoire, roughly ABRSM grades 2–3. In the RCM system it corresponds to about level 2.
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 Boat Song lasts about 2 minutes.
Boat Song 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 Andantino in C major by Franz Schubert, 'Sleep! Baby, sleep!' by Alfred Humphries Pease, 'O marenare 'e Mergellina by Costantino De Crescenzo — see the full similar-pieces list on this page.