How do I go about opening a pre school as a small business

The first step is to check local laws on the requirements. Many localities have some strict requirements for pre-school (or day care) businesses.

Next, you should develop a business plan that will include funding for startup costs, insurance, advertising, etc. You can get help for that at places like SCORE.org (http://www.score.org) and www.sba.gov (http://www.sba.gov).

Once you have your business plan and licensing in place, you can start to build the business.