Toy Databases for Class Examples/Homeworks I am familiar with the Northwind database and Chinook database as good toy databases for allowing students to practice writing queries. Are there other databases in a similar vein that are available? I want something with a sensible real-world data model and enough data to be interesting. 

In particular, I'm interested in databases that can be downloaded/built from a set of SQL statements in a script - building the tables, adding the foreign key relationships, inserting the data, etc. That way, students can add data under the constraints of the database (e.g., foreign keys). Thus, I am looking for databases that are downloadable in formats compatible with major RDBMS implementations (e.g., MS SQL Server, MySQL, SQLite). This differentiates this question from the previous question regarding datasets, which focuses on flat files, or databases available as flat file.
I stil think this is basically a duplicate of this question: Good datasets for intro CS courses?

You're asking for a database of interesting data. The other question is asking about interesting data. The only thing you need to do to get from the answers in that question to the answers to your question is to write a little bit of processing code that outputs the data in a format that's compatible with a database.

In other words, you're going to have to massage the data. This might require writing a program that calls an API to get data, and then outputs that data to .sql files or more basic .csv files or something. Then the students would take those files and work with them to create their databases.

I think as soon as you accept the fact that you're going to have to massage the data, you'll open yourself up to a lot of cool data sets. I think restricting yourself to data that's already in the exact format you need is very limiting, and isn't how things work in the real world. In the real world, data is always in the wrong format. You always have to convert it to something you can use.

Stop looking for data in the format you want it in. Start looking for interesting data, and then figure out how to get it in the format you want it in.