1. Preheat grill to medium-high heat.
2. Thread bell peppers, zucchini, and cherry tomatoes onto skewers.
3. Brush with olive oil and season with salt and black pepper.
4. Grill skewers for 10-15 minutes, turning occasionally, until vegetables are tender and slightly charred.
5. In a pot, bring quinoa and water to a boil. Reduce heat, cover, and simmer for 15 minutes or until water is absorbed.
6. Fluff quinoa with a fork and let cool slightly.
7. In a large bowl, combine quinoa, cucumber, cherry tomatoes, olive oil, salt, black pepper, and lemon juice. Mix well.
8. Serve vegetable skewers over quinoa salad.