Down 48-47 after a mounting a second-half comeback, Tilford took an in-bounds pass and drove to the basket for a layup and a 49-48 lead. Dobbs Ferry had several shots underneath their own basket but failed to connect in the final 10 seconds.
Woodlands, which began the tournament as a seventh-seeded underdog, advanced to next week's Class B state regional playoffs.
Seventh-grader Teisha Hyman, who scored all 12 of her points in the second half to help lead the comeback, said the win gave her school some pride.
"I know I didn't play well enough in the first half and wanted to contribute more," Hyman said following an emotional victory celebration. "The boys have won here before but never the girls. We had to do our best to make the comeback. It is so great to be representing the school in the states."
Alyssa Chipelo, who scored 17 points and made the All-Tournament team, scored 11 points in the first half to lift No. 4 seed Dobbs Ferry to a 24-13 lead.
Tilford kept pace with Chipelo, scoring all 13 of the Falcons points in the first half. The Falcons defense stiffened in the third quarter and Dobbs Ferry's lead was cut to 37-31 going into the fourth quarter.
Tilford, who was named the tournament's Most Valuable Player, scored another 13 in the second half, including the Section 1 winning basket.
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