Angryverse/Power-Ups University

Power Ups Unviersity is a new feature in Angry Birds. Here, power ups can be tested out for free. To open it, go to Shop (the shopping cart button) > Power-Up Bundle > Stella button (at the bottom right). Complete each level will give you a star. Collect all 4 stars to get a huge Power-Up reward!

It was replaced with the Tutorial in recent updates, which is bigger.