How long does it take to see results of volunteering?

Context: I was involved in a discussion with some folks on volunteering and educating children (in general) and up came the question of how long do you need to take to see results?

My take: It is definitely not effective if you only teach for a single time or two. You will only see improvements when you accumulate these lessons over a certain period of time. Depending on your learning objectives, it may take a year, 2 years or many more – 十年树木,百年树人 – you are in for the long haul.