How many lessons?
Does anyone know how many lessons there are in the Chinese tree with the new crown system?
And related, how many topics are there in the Chinese tree?
As far as I know, there are still 88 skills in the Mandarin Chinese course, but the number of lessons in each one varies. You can take a look at how many lessons there are in each skill at your progress page, after switching to Chinese (the site shows the progress for currently selected language):
As for the number of crowns, each skill has 5 of them, so 88x5=440
By using your progress page, you can calculate how many exercises you will have to do to get to crown level 5 in each skill:
To get to level one, you need to do the base number of lessons, let's call it S. Then, to get to level 2 - S lessons again, to level 3 - 2xS, to level 4 - 3xS and to level 5 - 5xS. In total, to go from zero to crown level 5, you need to do Sx12 lessons.
If you take the S number of lessons from the page above, you can get an exact number for each skill and even the whole tree. :)
No, it's a separate site, but it uses the data available publicly from Duo. There are some interesting things there linked at the bottom of the page, such as Streak Hall of Fame, XP Hall of Fame etc. ;)