CREATE TABLE table_26898 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" FLOAT)

What episode number in the series is 'mean teacher'?
SELECT MAX("No. in series") FROM table_26898 WHERE "Title" = 'Mean Teacher'
SELECT MAX("No. in series") FROM "table_26898" WHERE "Title" = 'Mean Teacher'