As of last night, I've created 20 courses in Super Mario Maker 2. Here's a random sampling of 7 of them:
Mario Plays NES Games
Course ID: TW6-PMX-VQF
Description: As Mario, go home to your living room for an afternoon of playing three NES classic games on your NES. Turn the NES on and hop inside your TV to play a level of "Mario Bros.", "Donkey Kong Jr.", and "Super Mario Bros."
Mario Maker Kart Quadruple Dash
Course ID: RQ8-RFQ-WLF
Description: A Mario Kart inspired level designed with multiplayer mode in mind. There are 4 available "karts" (Koopa cars) and the ability to activate an obstacle in your opponent's paths along the track.
Infiltration of Hangar 66
Course ID: W8N-PML-MFG
Description: This one is a completely original level. Mario must gain access to an enemy airbase, infiltrate Hangar 66, steal a copter and use it to board Bowser's Airship high above. Once aboard, activate explosives to defeat Bowser and destroy the airship.
Mario Plays NES Games Too
Course ID: 6FL-GB3-9MF
Description: The sequel to my most played creation, "Mario Plays NES Games". Mario returns home for another afternoon of playing classic NES games in his living room. This time, play levels from "Donkey Kong", "Popeye", and "Zelda II: The Adventure of Link".
Grand Theft Auto: Koopa City
Level Code: GCH-VQ4-14G
Description: What a crossover between Grand Theft Auto and Super Mario Bros might look like. Enter stores and apartment buildings, steal cars, run down the denizens of Koopa City on the street, etc. I set a coin collecting requirement that can be reached by scouring the individual buildings of the city, or completing any one of 3 optional side missions (Defeat the Hammer Bros. Gang inside the Warehouse, Rob the Bank Vault, or Execute the Stunt Jump). There is an optional bonus mission at the end of the level as well (launch a car through the Window of Bowser's office).
GI*Joe: Escape from The Pit
Level Code: RXP-VBP-63G
Description: After the title screen, you start off at the lowest level of GI*Joe's secret underground base, The Pit. Suddenly, Cobra Troops bore their way in through the walls. Fight your way up to the surface, emerging through the Motor Pool above. Fight your way through the invading Cobras on the surface, making sure to blow up the bridge during your daring escape.
The Great Hall of Bowser
Course ID: 8KV-KGW-JPG
Description: One of my most recent creations, and first ever crafting of a Bowser's castle level. Enter Bowser's castle executing treacherous jumps to advance. Work your way through "The Great Hall of Bowser" to reach a showdown with Boom Boom. Emerge victorious to steal the key you will need to enter Bowser's treasure room. Then, continue through the castle to ultimately battle King Koopa himself. I put extra effort into the background to make Bowser's castle as ornate and ostentatious as possible.