Multi stage sampling for a nationwide study:
We are planning a study comprised of assessing teaching (through classroom observation) and SLO (test) from public and private schools of six provinces of X country.
We need to include all six provinces.
-> there is variation in number of districts in each province. How many districts should we select and on which basis?
-> Should we need to do power calculation for school level? if yes, should we consider entire schools of the province as population and select schools from it? How many schools should be select from each district?
-> From each school we want to have representation from primary (1-5) and lower secondary grades (6-8). How many grades should be select? and on which basis?
-> How many students would be enough from each school? Can we use power calculation for students? if yes, what will be our population?
Also, would be grateful if you could suggest some relevant references and useful sample calculation calculators.
Looking forward to hear from you.
Thank you