There are more than 5000 sample data in the database. You can use it by downloading. It is an easy database. There is a few table in it. Learning and teaching is very easy.
Download the zip file and unzip. You will get LibraryDatabase Folder
The folder has three files: libray.mdf,library_log.ldf, script2104.sql and script2008.sql.
To attach the database you will use the library.mdf and library_log.ldf files. If you want to learn how to attach a database you can read the article.
If you have Sql Server 2008 or newer version you can ran script2008.sql file easily.
If you have Sql Server 2014 or newer version you can ran script2008.sql file easily.
The database prepared by sql 2014 database engine. If you have earlier version of mssql you will get error message while attaching the database.