K.M.
Friend, Friend, Valentine - like duck duck goose
Valentine's Bingo! Use Pictures - like Cupid, Hearts, Arrows, simple words like LOVE, MOM, DAD etc
Get a jar or bowl and put a lot of different shapes in there and have only a few heart shapes they have to find blindfolded. - Love is Blind!
Pin the heart on the Cupid - Have an art teacher draw up a cupid then use the die cut machine and make enough for each student - put their name on it - laminate - use masking tape like a donut and have them pin the heart on the cupid.
My son's pre k class likes to "station" the room and have parents volunteer to help run the stations - we would have three or four things going on and a parent or two for each station (only 11 kids) small groups rotate around to each station
Craft station - games station - food decoration station and so on. That may work if you have parents that like to volunteer their time to the class.