Here we have an opening that is comprised of what I like to call, "dynamic stills." Essentially, this means that the focus shots of the opening are pictures, but each picture is moving. It's a concept that's kind of hard to grasp without an example, so refer to the following "dynamic still":

Now, I'd like to play a game here. A-1 Pictures has almost set these shots up to have hidden objects in them, so I decided we should play a game of I-Spy. Take a moment to look back to the first "dynamic still" (the gif above this paragraph) and try to find me a STAPLE REMOVER.
Find it? Even if you didn't, we're starting the rest of the game now.

Coffee in one hand, phone in the other. You really are a slacker, Yutaka. Your GRANDMA would be disappointed:

The following grandma is easily visible, and she's talking to Saya as usual, but what's unusual is this LAPTOP's new home:

Megumi appears to have busted some lockers to the point that TWO KEYHOLES have dislodged:


It's lunch time for Taishi, but it's launch time for this ERASER (yeah I just said said that :P):

Chairs exploding is a side effect to Tohko-chan's presence, but this HAIR CLIP seems to be intact:


Ah, the whole cast in one frame, facing our direction, but these THREE ARROWS seem to be pointing whichever way:

Thanks for reading! I hope you had fun! Did you find everything? Post where you think they all are in the comments. I'll tell you if you got them all correct.

Oh! I almost forgot the OP/ED, take a gander here:

Title: May I help You? | Artist: Assorted cast members| Show: Servant x Service