WITH 
    tall AS (
    SELECT AVERAGE_VALUE
    FROM SCHOOL_HEALTH
    WHERE CATEGORY_CODE = '10'
    ),
    weight AS (
    SELECT AVERAGE_VALUE
    FROM SCHOOL_HEALTH
    WHERE CATEGORY_CODE = '20'
    )
    

SELECT AGE AS AGE
    ,where case
    when GENDER_CODE='20' then SET GENDER_CODE='MALE'
    when GENDER_CODE='30' then SET GENDER_CODE='FEMALE'
    AS GENDER
    ,AVG(tall) AS H_AVG
    , AS H_PER
    ,AVG(weight) AS W_AVG
    , AS W_PER
FROM SCHOOL_HEALTH
WHERE SURVEY_YEAR = '2019'
AND AVERAGE_VALUE
GROUP BY AGE
ORDER BY AGE DESC
    ,GENDER_CODE DESC