Alternative-rock sweethearts Cake schooled their audience on tree identification and rocking out during their June 11 tour stop at the Cosmopolitan’s pool. Perhaps it’s fitting that while promoting their latest studio album, Showroom of Compassion, they turned the venue into something akin to a showroom, a classroom.

Cake began their performance quietly, almost unnoticeably, with “Sad Songs and Waltzes.” After finally garnering the audience’s attention, they stepped up the tempo with “Wheels” and “Rock ’n’ Roll Lifestyle.” When the band returned from an unusual 20-minute break (because the smell of barbecue had made them hungry), the night became even more unusual with a tree giveaway. The contest was easy: Identify the species of the tree that sat onstage in a pot and you won the tree. But after 10 minutes and several failed guesses, lead vocalist John McCrea realized, “Las Vegas is out of touch with nature.” The winning answer (a plum tree) came from a schoolteacher who then had to make a lengthy pledge to plant the tree and take care of it.

Getting back to the music, Cake went with “War Pigs” to put the crowd back in the rocking mood. As they finished up, they saved their biggest hits “Never There” and “The Distance” for last.