Some online dictionaries for kids that include example sentences are Wordsmyth, Merriam-Webster Word Central and Little Explorers Picture Dictionary. Some websites feature Spanish translations alongside example sentences.
Wordsmyth offers various options and filters for exploring the dictionary, as well as lists of categories that feature key words that children can look up. The site also offers an illustrated dictionary, which provides excellent sentence examples and Spanish translations.
Word Central offers a traditional dictionary, as well as a thesaurus and rhyming dictionary. An additional "Build your own Dictionary" tool allows children to create, save and share their own words and accompanying definitions or examples.
Little Explorers Picture Dictionary has a simple structure that offers a picture, spelling and example sentence for each word.