Yes! In the cleaning supply aisle in the grocery store is Mr. Clean Magic Eraser. The original works best. Wet the sponge – you can cut it into small cubes – and lift out paint that is dried and unwanted in your painting. You can almost get it back to white paper. This works better than a scrubby bristle brush but of course it can’t be used in tiny spaces like a brush. It will take off most anything. After a few uses, the sponge crumbles and needs to be tossed.
The best tape for creating straight edges is “Watercolor Washout Tape” which looks like a big roll of cellophane tape but it’s thicker and stronger. It costs more than the blue painter’s tape from the hardware store but gives perfect edges if used correctly. Using correctly means making sure the tape is secure on the paper by smoothing with a burnishing tool or finger over the tape. One way to get a double use from the tape is to only put down half a side. After it’s taken off the paper the tape can be flipped around and the clean edge can be put down.
Inexpensive flat bristle brushes from hardware stores can create grasses and lines. Onion, orange, grapefruit bags cut up can give a “pineapple” texture. Sponges, toothbrushes (which are also used for spattering by moving your finger along the bristles), mesh screens, and other kinds of screens can create texture. Even using a broken tree stick dunked in paint can give scratchy uneven strokes. Any item that has holes can create textures on dry paper. Items that have indentations, like paper towel designs, work well on wet paper. Go give it a try. And wear a smock.