I had a primary school teacher like that. He was in love with French culture and his enthusiasm for the topic was so infectious that I learned more in a single day with him, than I did in any of the years of textbook French lessons I took in high school.

I hated it but my teacher just had us read a book quietly and then tested us on it. Almost no interaction at all other than occasionally making us take turns reading it out loud which also just kinda sucks