Gemma and Dave are adjusting to Grover growing up and becoming a teenager; Marty and Calvin are struggling with different management styles at work; one of Marty's new employees, Courtney, might become something more.
Calvin is adjusting to getting older and the new stages of parenting; Malcolm questions his career path; Lamar shows up to spend more time with Grover, which forces Gemma and Dave to loosen the reins a bit.
Calvin recovers at home, spying on neighbors from the window. He suspects sketchy activity across the street, so his crew devises a plan to catch the new neighbor.
Gemma holds a fundraiser for a new school pool; Tina and the other teachers are being overworked; Dave convinces Calvin to finally commit to doing physical therapy for his knee.
Gemma and Tina are at odds with one another and Dave and Calvin try to bring them back together; Marty is sick and not handling it well, so Malcolm fills in for him and goes to a baby class with Courtney.
Marty and Courtney's baby name gets spread around because nobody can keep a secret; Dave is assigned the ever-complicated task of assembling the diaper changing table.