@Ali1302, you misunderstand. Donations are not taxed. In the US individuals can reduce the taxes that they owe to the government by donating to non-profits, including public universities. On average, for every $1 you donate, you can reduce your taxes by 25c. That is one way that people “find a way around taxes” .
In the UK individuals can not get a reduction in the taxes they owe for donations. Instead, as Conformist1688 points out, the individual donates the money and the charity can reclaim part of the basic tax relief (typically +/- 25p on the pound). The evidence suggests that the UK version is not as effective an incentive to donate as a direct tax deduction.