Even a penny will help.

In the surrounding weeks, lots of performance societies have held or are planning to hold a charity concert. Often, this consists of a normal concert, just with a charity bucket at the entrance. This is not always particularly effective, so with Piano Society we've been trying to brainstorm ways to encourage people to give to charity, especially students, who don't have particularly deep pockets. One way our president suggested was to "try to get everyone to give even just a little bit of money, because then overall it will all add up and we can then give a decent amount of money to the charity".
This in the literature is known as 'legitimizing paltry contributions'. This technique is effective because it removes excuses for not giving such as "I can't afford to give right now", which are understandably common amongst students.

Cialdini and Schroeder (1976) tested this by approaching 123 subjects and asking them to donate to charity. In the control condition, the sentence "We've already received some contributions, and I wonder if you would be willing to help by giving a donation" was used. In the other conditions, this was then followed by "even a penny/dollar will help". A social legitimization condition was also added with a slightly modified request, "We've already received some contributions, ranging from a penny on up, and I wonder if you would be willing to help by giving a donation". Frequency and size of donation were then measured.

The table of results is shown above. It was found that by adding the sentence, "even a penny will help", this significantly increased  the number of subjects who donated from 32.2% to 58.1%. They also found that by legitimizing rather than directly requesting small amount of money, it was possible to achieve even higher rates of compliance at 64.5%.

This results show that by legitimizing paltry contributions, over 50% of the subjects then donated. This is very useful as it is a technique which requires very little effort to implement but is very successful. If this technique can be used in charity concerts and fundraisers on campus, then this suggests the amount that student societies donate to charity each year will substantially increase.

Cialdini, R. B., & Schroeder, D. A. (1976). Increasing compliance by legitimizing paltry contributions: When even a penny helps. Journal of Personality and Social Psychology, 34, 599-604.