Kees Schoonenbeek's sonatina is a concise work that utilizes accessible tonal language within a classical framework. It is distinguished by its clean textures and melodic clarity, suitable for developing students.
Attention to clear phrasing and consistent articulation is required for a successful performance.
Comparable difficulty and character — good candidates for what to learn next.
1st Sonatina is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 1st Sonatina lasts about 6 minutes.
1st Sonatina 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 Bal Masqué by Kees Schoonenbeek, Ballad by Kees Schoonenbeek, 'Sweelinck!' by Kees Schoonenbeek — see the full similar-pieces list on this page.