For high school, at least, I'd suggest the pre-madrigal Italian Frottola repertoire, most of which are homorhythmic rather than contrapuntal. They are an excellent introduction to the more difficult middle-period madrigals. Composers to look for are Marco Cara, Bartolomeo Tromboncino, and Rossi of Mantua.
Also the French chansons of the time were also more homorhythmic than the Italian madrigals, and more accessible for choirs who have not yet progressed into being able to handle complex polyphony.
For middle school I don't have a clue, but you might try to track down a collection called the Juilliard RepertoryLibrary, which includes excellent pieces from all time periods but which doesn't seem to be widely known. My late wife found excellent repertoire in it for her Youth Choir at church, including renaissance and even some excellent medieval that's quite accessible.
In These Delightful Pleasant Groves SAB Purcell/Thompson Presser #392-41777
Mairi’s Wedding SAB Bob Chlcott Hal Leonard #08740324
It Was a Lover and His lass SAB Robinson Fischer CM8782
Fa Una Canzona SSAB Joyce Eilers Hal Leonard 40206050
Now Is the Month of Maying SSAB Joyce Eilers Hal Leonard 08301815
Masterworks and Madrigals for Middle School Choirs Mary Lynn Lightfoot Heritage
Invitation to Madrigals, Bk. 1, SAB by Thurston Dart, published by Galaxy #1.5106
As Fair As Morn SAB John Wilbye/ed. Haberlen Mark Foster MF338
Pastime with Good Company SAB Shawnee Press D-428
Come Sing a Joyful Song SAB P. Liebergen Shawnee Press D-437
How Merrily We Live, SAB, arr. Donald Moore, pub. Hal Leonard 45812017
Follow Me, Sweet Love, SAB, arr. Michael East, pub. National CMS-120
O Rosetta Che Rosetta, from Scherzi Musicale a tre voci, no. 08, by Monteverdi (excellent recording by the Waverly Consort "Italia Mia"
LP--can be found on ebay once in awhile)
So Ben Mi Ch'a Bon Tempo - There are several arrangements of this song currently available - Google it!
SATB - I highly recommend The A Cappella Singer - still available - Here's a list of songs in it:
This classic collection of Renaissance tunes by Morley, Weekes, Gibbons and others was compiled by E.C.Schirmer in 1936.
Song List:
Sing we and chant it (Morley)
April is in my Mistress' face (Morley)
Now is the month of Maying (Morley)
My Bonny Lass (Morley)
Shoot, false love, I care not (Morley)
Dainty, fine, sweet nymph (Morley)
Flora gave me fairest flowers (Morley)
Adieu, sweet Amarillis (Morley)
Grace my lovely one, fair beauties (Weelkes)
Lady, your eye my love enforced (Weelkes)
I thought that Love had been a boy (Byrd)
Let go, why do you stay me (Bennett)
The Silver Swan (Gibbons)
Rest, sweet nymphs (Pilkington)
In these delightful, pleasant groves (Purcell)
Matona, lovely maiden (Di Lasso)
I know a young maiden wondrous fair (Di Lasso)
Good-day, dear heart (Di Lasso)
Ah, could my eyes behold thee (Di Lasso)
O eyes of my beloved (Di Lasso)
My heart doth beg you'll not forget (Di Lasso)
Gay little Nymph (Regnard)
One smiling summer morning (Verdelot)
To woodland glades I must fare (Tessier)
Coletta (Gevaert)
Spring returns (Marenzio)
So well I know who's happy (Vecchi)
You defy me, beloved foe (Giovanelli)
Cloud Messengers (Cui)
Radiant stars, above the mountains glowing (Cui)
There are also many wonderful choral arrangements set to Shakespeare texts - such as
Three Madrigals, SATB, by Emma Lou Diemer
Simply Google the first words of the text and then SATB (i.e. It Was a Lover and His Lass, SATB), and there should be several arrangements available--many of them in multiple voicings and contemporary accompaniments.
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