How do you say my school is called... in German?

The most straightforward translation of "My school is called..." in German is:

Meine Schule heißt...

You would then follow with the name of your school. For example:

* Meine Schule heißt Goethe-Gymnasium. (My school is called Goethe High School.)

* Meine Schule heißt Waldorfschule am See. (My school is called Waldorf School by the Lake.)