Festivals!
RE Online provide an excellent overview of festivals and significant dates for all faiths which we would recommend you look at as part of your collective worship planning. HERE
Colours
Information on the liturgical colours for different times of the year are available HERE
Lectionary
We also recommend the Lectionary App which gives you information along with the Bible reading and associated prayers for each day which can be useful in planning Collective Worship. This app is free to down load from the App store and Google Play.