Which Sport has a League of continental basketball league, and a Venue of avalon middle school?
CREATE TABLE "minor_sports_teams" (
  "club" text,
  "sport" text,
  "league" text,
  "venue" text,
  "championships_years" text
);
SELECT "sport" FROM "minor_sports_teams" WHERE "league"='continental basketball league' AND "venue"='avalon middle school';