Every third lesson some of you will be tested on the words studied so far because it's good for you and us to know if you are on track. You won't be graded on this, but your teacher makes notes of your progress.
At the end of each unit you will do a test on all the items that you have worked on. This test will include some idiom exercises, some grammar and maybe even a listening, reading or writing exercise. Make sure you understand all the grammar that is in the unit. Of course, you can always ask your teacher in one of the final lessons.
If necessary, you can do some extra practice using this SPREADSHEET.
Throughout the year you will also do a number of reading and listening tests.
The tests are done either during the lesson or during the so-called "centraal toetsuur".