The amount you will get paid depends on the amount earned and your tax code issued by HMRC.
An example is If you work 20 days a month at £100 a day and are part of the Teachers pension scheme you are likely to get paid
Lees NI 165.60
Less Pension contribution 220.00
Less Tax (assumimg you have standard tax allowance etc) 139.54
Take home before other deductions e.g. student loans £1474.86