A good thesis statement will summarize the argument of your paper. Think of it this way: your thesis should guide the reader throughout the body of your essay, and help them contextualize the information you provide.
That being said, your thesis statement should reflect the specific argument you will be making in regards to terrorism and the education sector in Pakistan. Will you be arguing that terrorism has a negative effect? If so, a good thesis statement might be: "Terrorism has had a negative impact on the education sector in Pakistan." You don't have to provide a great deal of information here; remember, you are just laying the groundwork for the rest of your paper, where you will support your claims with evidence. However, it is always a good idea to follow up your thesis statement with a brief outline of the points you will make. For example: "Specifically, terrorism contributes to poverty, and therefore the inability of families to pay for school tuition. Also, the anti-education attitudes of terrorists, combined with their penchant for violence, causes many to forgo education out of fear."
Last, you may want to narrow your topic down to a specific terrorist group or ideology. "Terrorism" is, after all, an extremely broad topic. A more specific thesis statement could be: "Taliban terrorism has had a negative impact on the education sector in Pakistan."
Hope this helps!