If you live at Bruxelles here is a good option of activity: go to the Galerie Pascal Polar and visit the current exhibition Karl Waldmann & Constructivisme Russe. This German artist made more than 900 works dating from 1915 to the 50’s, most of which are collages or photomontages.

His early pieces are abstract but soon after, his other works turn to echo constructivism, Dadaism and even surrealism.
The forms derived from constructivism, with a destruction of the classical image, VERB! in a dynamic vision. But the state of mind of the photomontages is close to the Dadaists by the will of integration of the social facts of his time in an acid and politic vision.

There is an online version of the exhibition here. More information about him can be found at Karl Waldmann Museum, including his works.