Class One. Introduction, Hakhel was not a Korban and was done by a non-Kohain and could possibly have been done at night etc. The bringing of children was not Chinuch and therefore the smallest are brought, there is no age specification for Hakhail at all. [The idea of reenacting Mattan Torah] Class Two. Page 62-4. Hakhail means a meeting of the Neshama and therefore doesn't distinguish between children (even infants) and adults. [From the teacher: five examples for Hakhail: 1) The event of Mattan Torah, 2) the Mitzva once in seven years, 3) Once a year bringing children to Shul on Shavuos, 4) Parshas Kedoshim (as an example) was said on Hakhail (Rashu), 5) Moshe gathering the Yidden every single Shabbos for Hakhail]. Class Three. Page 64-5. The reason it was read and done right after Shmitta so we should return to the world but remember our faith. Class Four. Page 64-5. Continued, after Shmitta. Class Five. Page 65. Sukkos and Chol HaMoed represent gpoing into 'sin' the real world and further warrent the message of Hakhai. Class Six. Page 65-6. Children who know and understand nothing are brought because this is about Yiras Shamayim, which goes into the Neshama. Class Seven. Page 66-7. continued, Hakhal is done for those who get nothing from it consciously because it affects their subconscious.