Will tuition cost more under the semester calendar?

No. For undergraduate students, under the semester system the same fee structure will apply. See CSU Fee Schedules. The annual cost of your education will not be impacted by the quarter to semester transition. However, the cost per term will be higher on semesters because there are only 2 semesters, which means annual fee is divided in half (as opposed to the quarter system, where the annual fee is divided into thirds because there are three quarters).

For graduate students, the amount of tutition will vary depending on your program.