Last Tuesday was hip throw nogi and Knee on the Belly (with 3 subs).
Last night (Thursday night) was uchimata and De La Riva guard / berimbolo (guard sweeps)
You will need to learn Berimbolo if you want your 3 stripes on your white belt.
Berimbolo is just basically the continuation from de la riva guard.
Instead of taking the back, you keep the same grips and invert instead.
Why is it so popular?
Because there is no counter to the berimbolo as far as I know.
Why is it hated?
Because people hate what they don't know.
Why is it revolutionary?
Because it is going against the traditional style of take down, guard pass and submission after achieving dominant top position.
You can read more info on this controversial topic.