Today’s piece is Solfeggietto by Carl Philipp Emanuel Bach (aka C.P.E. Bach). The piece is commonly assigned to piano students and appears in many books because it fosters the playing of an even sixteenth note rhythm by alternating hands.
Clarinet starting about a minute in:
Find it on IMSLP, in several anthologies of music at the O’Connor Music Studio, in Piano Pronto: Encore