87. The Teacher's Responsibilities
Talmud Torah 2:2
Children should be brought to a teacher at age six or seven, depending on the child’s individual development; children younger than six should not be brought. A teacher may use physical punishment to direct his students but he may not hit them cruelly, as an enemy would do. For example, he may not use a rod or a staff, just a small strap. [Editor’s note: Do not do this. Even if permitted by traditional halacha, that does not take into account modern sociological factors, as well as civil law.]
A teacher should instruct his students all day and for a bit of the night, so that they should learn to study Torah by day and by night. The children should only cease their studies at the end of the day before Shabbos and Festivals, as well as on the Festivals themselves. On Shabbos, students should not begin studying new material; they should review what they already learned. Children should not be interrupted from their studies even to rebuild the Temple.
Talmud Torah 2:3
A schoolteacher who leaves his students and goes out, or who stays with them but occupies himself with other work, or who is lazy in his duties, is among those included in “Cursed is one who performs God's work deceitfully” (Jeremiah 48:10). It is therefore appropriate only to hire a God-fearing teacher who teaches his students carefully and at a quick pace.