cut teeth on
cut (one's) teeth on (something)
To gain experience with something, especially at a young age (when one's teeth would be coming in). Oh, I cut my teeth on those kinds of equations! Give me a challenging problem for a change! Jen may be young, but she cut her teeth on academic writing, so her perspective and expertise will be invaluable to us.
cut (one's) teeth on
To learn or do as a beginner or at the start of one's career.