Woot offers Texas Instruments TI-30XIIS Scientific Calculator for $8.99 (orig. $17.99). Free shipping with prime members.

Product Description:
Fundamental, two-line calculator combines statistics and advanced scientific functions for high school math and science.

• Robust, professional grade scientific calculator. Logs and antilogs
• It has 2-line display shows entry and calculated result at same time
• Easily handles 1 and 2 variable statistical calculations and three angle modes (degrees, radians, and grads) and scientific and engineering Falsetation modes
• It has 1-year limited warranty
• Solar and battery powered