Yep you do need higher irish :)
No. For primary and secondary school teaching, Irish is a mandatory subject. Primary school teachers are expected to have Irish. Exceptions can be made for teachers who are not Irish and so would not have learnt Irish in school themselves. So it is possible for teachers from other countries to work in Ireland as a primary school teacher without Irish. If the teachers are Irish themselves, then they are expected to have Irish in order to teach in a primary school. For secondary schools, different teachers would have specialist subjects, so not every teacher would be teaching Irish. So they would not need to have Irish. For other levels of education, it is not an issue at all.
bunscoil
the school i go to starts teaching Irish dance at 5 to12 years of age
It has not been made public what primary school Eoin Colfer attended, but it was in southeast Ireland. He also taught at an Irish primary school in Wexford.
Summer break in an Irish primary school is usually 9 weeks.
múinteoireacht
It depends on what you mean really ! IN my top honors Irish class there are fiche cuig (25) students
teagasc and múineadh; the act of teaching is múinteoireacht.
príomhúil
Irish School of Ecumenics was created in 1970.
McConoghmy School of Irish Dance
I'm not sure what the school year is for English schools but for Ireland the younger ones in primary school get 9 weeks summer holidays and the teenagers in secondary school get 3 months.