Kavanah, kavvanah or kavana (also pronounced /kaˈvonə/ by some Ashkenazi Jews) (כַּוָּנָה; in Biblical Hebrew kawwānā), plural kavanot or kavanos (Ashkenazim), literally means "intention" or "sincere feeling, direction of the heart".
[3][4] Kavanah is a theological concept in Judaism about a worshiper's state of mind and heart, his or her sincerity, devotion and emotional absorption during prayers.
[1][5] In Hasidic Judaism, a Jewish tradition that emphasizes piety, kavanah is the emotional devotion, self-effaced absorption during prayers rather than a liturgical recitation driven religiosity.
A related term in Judaism is kavanot, states Pinchas Giller, which refers to "ideas, texts and formulae" to be contemplated during praying.
According to the Hasidic tales but not only, children also know how to reach a good level of kavanah and it isn't absolutely useless to teach them Shema, even before Bar mitzvah.