Classical string graphs are the intersection graphs of simple curves in the plane. The student will study the following new modification of this concept: a colection of simple curves (strings) in the plane is (k,m)-clustered if one can cover the representation by topological disks such that every curve intersects at most k disks, each one in a connected piece, and each disk is intersected by at most m curves. A (k,m)-clustered string graph is one having a (k,m)-clustered string representation. The task of the student is to study basic properties of the classes of (k,m)-clustered string graphs, compare these classes for various values of the parameters k,m, to study representability of particular graph types as (k,m)-clustered string graphs, and to try to determine computational complexity of recognition of (some of) these classes of graph.