“Schiffli versenken” (Sink the Ships) is a HyperCard game from Switzerland. It was created in 1993 as a math educational game. Markus Koller programmed it.

The game can be described as a “gated game” because players must solve a 1×1 math problem to continue playing. The motivation is clear: solve the math problem so you can make your next move. So the game isn’t just a standard game of Battleship, but actually a math-based educational version of Battleship—which was quite unusual for its time. The game instructions state that the program hides 8 ships in the selected playing field. As soon as you click on a field, you must solve a math problem to reveal the square. And at the end of the game, there’s a high score list where you can enter your name.

So playing the game is always the reward for solving the math problem. In this respect, there is a dual game mechanic—simple and effective—whose concept has survived in educational games to this day. The game was developed in 1993 as an educational game. At that time, Markus Koller had developed 12 other HyperCard educational programs, which were later ported to Director and continued to be distributed following the end of HyperCard. Together with two fellow teachers, Koller ran the company KILEP, which developed educational games and programs for schools. The software was distributed through various channels: Letec (Zurich), Medienwerkstatt Mühlacker (Bern), and the Lehrmittelverlag (educational materials publisher). Delivery was handled directly by KILEP. The company ceased operations in 2013 when Markus Koller retired.

Markus Koller first encountered the Mac Plus in 1988 and began working with HyperCard in 1990. Together with two fellow teachers, he then began programming educational software in a game-like format. As he explains, the focus was always on using the software in the classroom and for practice at home. The goal was always to provide personalized instruction. The feedback was generally very positive. The idea was to combine the game with mental arithmetic.

A screenshot of the KILEP company’s website from 2008 can be found on Archive.org: https://web.archive.org/web/20080306032258/http://www.kilep.ch/.

There, it says: “Plenty of practice material! We create practice programs for use in class and at home. These are designed to give students the opportunity to practice and reinforce what they’ve learned. All programs were created by teachers out of a need to provide students with additional, individualized practice material.”

You can play the game online. To do so, first launch Disk Hypercard, then load the file and select “Battleship”: https://archive.org/details/hypercard_schiffli-versenken

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