Very yesterday, I asked very similar thing another community if as a learner and a mom, It's good for me to teach or speak English to my children. And all people said it's definitely good to my daughters even to me, even if my English isn't good. Actually it's not that I teach English to them, but we study together, I think teaching and learning together is better than doing it alone.( I hope you understand my words... you know, I'm a beginer studying English)