What's more, putting the solution in front of the student is actually more effective than asking them to work it out for themselves. Research has shown that for novice learners, studying worked examples is more effective for learning than other types of learning methods. Learning this way is more efficient in that better learning outcomes are achieved with less investment of time and effort during acquisition. This is sometimes called 'the worked example effect' and can be explained by looking at the different cognitive processes involved when the student is asked to study examples, vs. conventional problem solving exercises.
When a novice student is required to solve conventional problems, they tend to resort to weak problem solving strategies such as means-ends analysis, in which learners continuously search for operators to reduce the difference between the current problem state and the goal state. Whilst the learner may indeed solve the problem eventually, this is not effective for learning. By contrast, worked examples prevent the use of such weak problem-solving strategies, allowing the learner instead to devote all the available cognitive capacity to studying the worked-out solution procedure (i.e., the relationship between problem states and operators) and constructing a cognitive schema for solving such problems. The learner further extracts general rules from the examples, enabling them to solve similar problems in the future (see Tamara van Gog & Nikol Rummel's 'Example-Based Learning: Integrating Cognitive and Social-Cognitive Research Perspectives', 2010). So next time you're struggling to complete an essay or problem, make sure you have examples of essays or worked problems in front of you to guide you. This is the most effective way to learn.
Aside from following examples that other students have produced, an essential way to get better at the essay writing process is to read up on what makes a good essay and ensure you don't lose marks for sloppy errors such as poor referencing, grammar, spelling or punctuation. There's no need to buy a book - there are a host of resources on the Internet to help you, and they're all free. So make sure you invest a little time in learning what makes a first class essay - from looking at others' work and by reading what's important for that coveted first class grade.