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MOPper World 2.0

Not an official logo, but comedic

About MOP#

This section of the website is dedicated to public-facing material from various years of MOP. It’s similar in spirit to the MOPper world that ran between 1997 and 2004. This page isn’t a puzzle.

MOP is a three-week camp now held at CMU. In 2020 and 2021, the camp was run on Discord. Prior to 2015, the camp was held in Nebraska.

See FAQ CR-7 for invitation rules.

Today, the camp is headed by director Po-Shen Loh and assistant academic director Evan Chen. (There is no academic director or assistant director.) Staff includes instructors, RA’s, and teaching assistants (aka graders).

For many years, the official name for MOP was “MOSP”, but the letter S was universally ignored by staff and students, and its omission became an ongoing gag. The S was finally officially deleted in 2017.

T-shirt designs#

Traditionally, MOP T-shirts are printed in black on grey. Except for 2020 and 2021, there is usually only a front design, and the back contains everyone’s signature.

2016. 2017. 2018; reference to 2017 G8. 2019; reference to ELMO 2019/2. 2020. 2020; reverse. 2021; reference to USAMO 2021/3. 2021; reverse. 2022; reference to USAMO 2022/2 2023; reference to USAMO 2023/1


  • The ELMO is written by returning MOPpers for new MOPpers, featuring “teams” and coordination. See ELMO page.
  • The Mock IMO is run by staff using ISL; it also features a mock coordination. It’s one of several practice tests run by the staff at MOP each year. You can download the problems here:
  • The staff also provide MOP homework to work on before camp starts, mostly for fun and so people have something to talk about at airports. Here are recent homework problems:


Here are calendars for recent years of MOP:

For more concrete times, here was the 2022 weekday timetable as an example (which should be read alongside the 2022 calendar):

  • 07:00-09:00 Breakfast
  • 09:00-10:30 Morning class 1
  • 10:40-12:10 Morning class 2
  • 12:10-13:20 Lunch
  • Exactly one of:
    • 13:20-14:50 Afternoon class,
    • 13:20-17:50 Mock olympiad / Team Selection Test, OR
    • 13:20-14:00 Assembly meeting (for announcements, etc.)
  • 17:00-20:00 Dinner hours
  • 19:15-20:00 Test review (presenting solutions to test problems) OR seminar on higher math (both optional)
  • 22:30-23:00 Evening check-in

There is a lot of free time built into the schedule, and this is intentional. Some examples of recent activities include singing troupe (see below), the double-elimination fish tournament, the plank countdown, trips to Waffallonia, dance tutorials, live-action Mafia and StarCraft (both no longer banned), and too many water balloons.

Singing troupe#

The MOP Singing Troupe is a tradition dating back to around 2010, started by Evan o’Dorney; it starts and ends the closing ceremony. Here are recent songs we performed:

MOP Puzzle Hunt# hosts:

  • A miniature one-round hunt written by Evan Chen, Isabella Quan, Sanjana Das, and Serena An for MOP 2021.
  • A 2022 puzzle hunt led by Luke Robitaille.


Nebraska trip#

In 2018, I flew back to the University of Nebraska-Lincoln the weekend before MOP to visit the venue again, since that was where MOP was held when I was a student. You can see photos of the Nebraska venue if you want to see why I keep saying things were better in the good old days.

The dorm we stayed in was called Neihardt Hall, and it had four sub-halls inside it named Heppner, Love, Piper, and Raymond. We had a lot of different lounge spaces, which also had names:

  • The Blue Room was the primary lounge on the ground floor, which was where orientation was held and a lot of activities.
  • There were side lounges on the ground floor called the Grey Parlor, the Gold Parlor, and the Sun Room, among others. We held singing troupe here since there was a piano.
  • There was an old-fashioned elevator with a curtain-like door that you pulled by hand. That elevator was labeled “OTIS”, and my training program is secretly named after this elevator.
  • The ground floor had a bunch of small classroom areas where test review used to be held. In addition to the red paintings, they had these little coasters, and people would throw them around a lot.
  • There was a meeting room with a green chalkboard where we held all the ELMO meetings.
  • The basement had a stage with some tables and chairs nearby where we held the ELMO and the talent show, as well as another giant lounge area nearby complete with several sofas, another TV, and a pool table.
  • Neihardt Hall itself enclosed a little garden area, that you could go outside and walk around in.

Also, the Selleck dining is amazing. Just saying.

Updated Mon 20 May 2024, 00:05:33 UTC by 08b785b79976