What factors slowed the rate at which substances dissolve in water science fair project?

Some of the factors are:

1) temperature - decreasing temperature slowed the rate at which substances dissolve in water, because there is less kinetic energy and molecules of water (solvent) collide with substance (the solute) with smaller frequency.

2) surface area - larger molecules slowed the rate at which substances dissolve in water because molecules less collide with water.