The ornamental design for a foldingstool with step, as shown and described.
FIG. 1 is a front perspective view of a folding stool with step showing my new design in an open position, the broken lines depicting environment and forming no part of the claimed design;
FIG. 2 is a right elevation view of the invention illustrated in FIG. 1 in an open position;
FIG. 3 is a left elevation view of the invention illustrated in FIG. 1;
FIG. 4 is a top plan view of the invention illustrated in FIG. 1;
FIG. 5 is rear elevation view of the invention illustrated in FIG. 1;
FIG. 6 is a front elevation view of the invention illustrated in FIG. 1;
FIG. 7 is a bottom plan view of the invention illustrated in FIG. 1;
FIG. 8 is a right elevation view of the invention illustrated in FIG. 1 in a folded position; and,
FIG. 9 is a front elevation view of the invention illustrated in FIG. 1, illustrated in a folded position.