Bostonese is a march-like composition by the prolific band composer E.E. Bagley. It features a jaunty, American-style melodic profile common to the turn-of-the-century piano transcriptions.
Balance the rhythmic precision in the left hand against the articulated melodic line.
Comparable difficulty and character — good candidates for what to learn next.
Bostonese is rated Henle level 3 of 9 — late beginner repertoire, roughly ABRSM grades 4–5. In the RCM system it corresponds to about level 3.
You should be comfortable at Henle level 3 — meaning you can already play level 2–3 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 Bostonese lasts about 3 minutes.
Bostonese 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 Piano Sonata No. 16 in C major by Wolfgang Amadeus Mozart, Maple Leaf Rag by Scott Joplin, 'S Wonderful by George Gershwin — see the full similar-pieces list on this page.