Tuition at public colleges jumped last year by a record amount as state governments slashed school funding, the latest sign of strain in the U.S. higher-education sector.

The average amount that students at public colleges paid in tuition, after state and institutional grants and scholarships, climbed 8.3% last year, the biggest jump on record, according to a report based on data from all public institutions in all 50 states to be released Wednesday by the State Higher Education Executive Officers Association. Median tuition...