If you are moving to a new school your current school will pay you to the end of the Easter break and you can start at your new school at the beginning of their summer term even if this is before 1 May.
If you are not taking up a new post your employer can require you to attend school until 30 April.
If you do not wish to return after the Easter holiday you will need your employer's agreement. In this case you will not be paid beyond the end of the Easter break.
You should make clear in your letter of resignation the date your resignation takes effect and ensure that you resign at the end of your school's Easter break if you wish to be paid for the holiday period.
For general advice on notice periods, including resignation dates for other terms, see ATL's advice page on notice periods.