Hola Nina

Spanish is generally very flexible in terms of positioning the different elements of the sentence. The usual in this case is to place the "a + noun" right in the beginning as you can see in the examples in the lesson. Sometimes if you want to highlight a specific element in the sentence you may change the placement to have that effect. The way you displayed your sentence is grammatically correct but it wouldn't be the common way. You would be perfectly understood though. 

Saludos