Kits for cooling computing devices may include at least one heat-generating component and a fan. A first duct may be sized and shaped to surround the at least one heat-generating component on three sides to direct a portion of air flow from the fan. A second duct may be sized and shaped to extend over the first duct and direct another portion of air flow between the first and second ducts. The at least one heat-generating component may comprise multiple vertically and longitudinally aligned memory modules Computing devices, electronic systems and methods of cooling are also disclosed.