In the bowl of the slow cooker, combine the sugar, ginger, and butter.
Add the pears and gently toss to coat. Arrange the pears cut-side down.
Set the slow cooker to high and cook, covered, until the pears are tender and easily pierced with the tip of a knife, about 1 to 2 hours. Divide the pears and ice cream among individual bowls and drizzle with the sauce.
Note:This recipe was tested in a 6-quart slow cooker. Because different models cook at different rates, the cooking time above is presented as a range. Check for doneness at the low end of the range (but not before, as the escaped heat will significantly slow the cooking). If the food is not done, cover and cook to the end of the suggested time range. If using a slow-cooker smaller than 6 quarts, the cooking time may take an additional hour or more, and results may vary.