Links to review chapter 1

Term manipulation puzzle
http://www.univie.ac.at/future.media/moe/tests/var/termumformen.html

Substituting numbers in terms
http://www.univie.ac.at/future.media/moe/tests/var/zeinsetzen.html

Substituting terms in terms
http://www.univie.ac.at/future.media/moe/tests/var/zeinsetzen.html

Equivalence of equations
http://www.univie.ac.at/future.media/moe/tests/var/zeinsetzen.html