Each public school, including, without limitation, each charter school, in a county whose population is 700,000 or more:
1. Shall, to the extent that money is available for that purpose, employ a school social worker at the school on a full-time basis.
2. Shall not, insofar as is practicable, enter into a contract with an independent contractor for the provision of the services that a school social worker is authorized to perform pursuant to NRS 391.296.