Mozart wrote quite a few.
Childhood symphonies (1764–1771)
These are the numbered symphonies from Mozart’s early childhood.
Symphony No. 1 in E-flat major, K. 16
Symphony No. 2 in B-flat major, K. 17 (spurious, attributed to Leopold Mozart)
Symphony No. 3 in E-flat major, K. 18 (spurious, by Carl Friedrich Abel)
Symphony No. 4 in D major, K. 19
Symphony No. 5 in B-flat major, K. 22
Symphony No. 6 in F major, K. 43
Symphony No. 7 in D major, K. 45
Symphony No. 8 in D major, K. 48
Symphony No. 9 in C major, K. 73/75a
Symphony No. 10 in G major, K. 74
Symphony No. 11 in D major, K. 84/73q
Symphony No. 12 in G major, K. 110/75b
Symphony No. 13 in F major, K. 112
Edited: Sorry I didn’t see you hadd listed Mozart in the question. It would be intersting to go down the list of childhood symphonies and listen to each one. Seeds of greatness.