On March 10, Nintendo will discount Super Mario Run's $9.99 in-app purchase that unlocks the full game down to $4.99, and that 50 percent discount will run for two weeks, through March 25. Nintendo has created a detailed table that shows the special discount price of Super Mario Run on the App Store and Google Play Store in every country of availability, which you can see on its website.
The last IAP discount for Super Mario Run came in September 2017, alongside what Nintendo called the "biggest update ever," introducing a new gameplay mode called Remix 10, new character Princess Daisy, new world, and more. It's unclear if the game will be getting more content this weekend, like it did last September, alongside the price drop.
For Mario Day last year, Nintendo celebrated in a variety of ways, including working with nonprofit Starlight Children's Foundation to provide hospitalized children with brightly colored hospital gowns featuring the company's well-known characters. There were also Mario-themed frames on Facebook, games on sale across Nintendo console platforms, and major events at PAX East in Boston and the Kids' Choice Awards on Nickelodeon.
You can download and play the first few levels of Super Mario Run for free on the iOS App Store [Direct Link], and the discounted $4.99 in-app purchase should begin appearing on Saturday.