EdTech startup looking for email leads

I'm looking for someone to generate leads for my education startup. I am looking for email address of secondary school (11 - 16 year olds) teachers teaching mathematics, I am not looking for emails from higher or lower schools, I am looking for emails from both private schools and public schools. I am only looking for emails for schools in England and Wales.

I would like the following details
- name of contact
- email address of contact
- school name
- location of school

If anything is unclear in this request please ask me