I didn't think too much about the difficulty of the songs I picked.
Sorry about that. If you do a song like "Seasons" maybe you can change the vocal arrangement a bit like this:
Chorus in Unison: [everyone]I feel seasons everywhere,
and I feel blessings in the air;
(those seeds that you've sown),
(you're gonna come into your own, seasons),
walk into your seasons.
(in the song the chorus is sung once with a soloist and one with everyone. Maybe you should just do it once with everyone then go to the verse)
Verse 1:[Female 1]I believe we're in a time
when God's gonna bless the saints,
[Female 2]those who have stayed, those who have prayed,
He's gonna fulfill the promise He made;
[Female 3]for I heard the Spirit say, it's your time,
the wait is over, walk into your season.
(Chorus w/ harmony)
Verse 2:[Female 1]I know that you've invested alot,
the return has been slow, you throw up your hands
[Female 2]and say I give up, I just can't take it anymore;
but I hear the Spirit say, that it's your time
[Female 3]the wait it over, walk into your season.
Bridge: [Everyone in harmony]You've survived the worst of times,
God was always on your side;
stake your claim,
write your name,
walk into this holy place.
[Female 3](I hear the Spirit saying, that it's your time, the wait is over)
I totally forgot about this part. I guess if you could break into two part harmony and give the solos to two people or have female 3 keep going until it gets down to "I heard the spirit say....walk into your season" Maybe if they're really creative they can find a cool way to sing the vamps without the soloist. I think having them just sing the vamp the way it's written might get boring after a while. Maybe you can jump down to "walk into your season" repeated 4xs with each female adlibing something like:
All: Walk into your season
Fem 1: Happy graduation day
All: Walk into your season
Fem 2: He wants the best for you
All: Walk into your season
Fem 3: Now is your time
All: Walk into your seasonVamp 1:The wait is over it's your time. (repeat)
Vamp 2:The wait is over. (repeat)
Ending:(I heard the Spirit say,
that it's your time,
the wait it over),
walk into your season. (repeated)
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Josh Groban's "You Raise Me Up" is a graduation favorite, but it's a solo song. I guess you could break up the verses and sing the chorus in harmony.