This is one of Mozart's charming and accessible 'Ariettes,' likely featuring a simple, song-like theme and a few varied treatments. It embodies the elegance and clarity of the Classical period.
Cultivate a singing tone and ensure smooth transitions between the melodic line and accompanying figures.
Ariette (K.307) 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 Ariette (K.307) lasts about 3.5 minutes.
Ariette (K.307) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.