At the Cotton Gin is a brilliant piece by Florence Price that uses ostinato figures to mimic the rhythmic movement of machinery. It is a highly effective, motoric piece that blends American folk idioms with classical structure.
Keep the rhythmic pulse steady and mechanical throughout, particularly during the rapid repetitions.
Comparable difficulty and character — good candidates for what to learn next.
At the Cotton Gin is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 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 the Cotton Gin lasts about 2 minutes.
At the Cotton Gin 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 Bright Eyes by Florence Price, 12 Variations on "Ah vous dirais-je, Maman" by Wolfgang Amadeus Mozart, Alexander's Ragtime Band by Irving Berlin — see the full similar-pieces list on this page.