A drinking cup that has a lid with a receiving portion is provided. The receiving portion may have a flow control engagement surface. A flow control element that may be configured for releasable attachment with the lid may be included and can have an attachment portion. The attachment portion may have a lid engagement surface. When the flow control element and the lid are attached, the flow control engagement surface engages the lid engagement surface. At least one of the flow control engagement surface and the lid engagement surface may have a concave shape.
