declare @temp table
(
    score int
)
insert into @temp(score) values(100);
insert into @temp(score) values(85);
insert into @temp(score) values(50);
insert into @temp(score) values(92);
insert into @temp(score) values(36);
insert into @temp(score) values(89);

--MAX VALUE
WITH MaxV AS
(
    SELECT score FROM @temp AS T
    WHERE NOT EXISTS (SELECT * FROM @temp WHERE score > T.score)
)
,MinV AS
(
    SELECT score FROM @temp AS T
    WHERE NOT EXISTS (SELECT * FROM @temp WHERE score < T.score)
)
SELECT 
    X.score AS MaxValue,
    I.score AS MinValue
FROM MaxV AS X,MinV AS I

MaxValue    MinValue
----------- -----------
100         36

(1 row(s) affected)

------解决方案--------------------
SQL code

create table #t([studentID] int,[score] int)
insert #t
select 1,72 union all
select 2,67 union all
select 3,54 union all
select 4,90 union all
select 5,53 union all
select 6,79 union all
select 7,88

select
(select top 1 [score] from #t order by [score] desc) as 最高分,
(select top 1 [score] from #t order by [score]) as 最低分

drop table #t

/*
最高分         最低分
----------- -----------
90          53
*/

------解决方案--------------------
不用max,min，那就用group by+order by?

------解决方案--------------------
SQL code

if object_id('tab') is  not null
drop table tab
go
create table tab([studentID] int,[score] int)
insert tab 
select 1,72 union all
select 2,67 union all
select 3,54 union all
select 4,90 union all
select 5,53 union all
select 6,79 union all
select 7,88

select
(select top 1 [score] from tab order by [score] desc group by 课程) as 最高分,
(select top 1 [score] from tab order by [score] group by 课程) as 最低分
into #tab_课程 from tab 

select 最高分,最低分 from #tab_课程

--drop table tab
--drop table #tab_课程1