1.We have to know there are two different kinds of vocabularies in the elementary level: words for recognition and words for production. For the former words, students need to pronounce or recognize these 300 words, but they don't need to spell or memorize them. For words for production, they are more like frequency words. and students need to spell, say and memorize these 180 words. In nearly every part of our textbooks, there may be another kind of words: words for phonics. They are just for teaching phonics, teachers shouldn't test spelling.
2. Since we know the different parts of words, we need to know how to arouse students' attention for these target words. Since they might be categorized in the same topic (for example, animals), we have to arouse students' attention about this. Categorization is quite important in this part. Many teachers only train their students how to pronounce the words, how to spell the words right, but students don't really get familiar with the words. I always have my students write a sentence based on the target word. Then , I would have my students "play" with these words. Take animals, for example, 12 animal signs, farm animals or wild animals, animals can run/jump/swim/fly/glide..., there are many ways to categorize the words.
3. Hands-on activities. We can have students design their pwn flashcards (both words and pictures), to design a small pamphlet is another task and need more time. If you or students were technology addicted, you could even have students design puzzles, spelling bees, crosswords... on the websites.
4. the purpose of building vocabulary is to read more books and write in English. Don't just stop at testing vocabulary, there are still many reading/ writing activities for you to involve students in a friendly English learning environment.