Without vocabulary you cannot speak or understand English. This ESL kids vocabulary page has lots of vocabulary topics for you to teach your children so they will know as much English as possible.
Especially for kids, the most important part of learning kids vocabulary is to understand the main content words: these are mainly the nouns and verbs, and the adjectives and adverbs to a lesser extent. These are the kinds of words that your children can learn on this page.
Remember that it is good to learn a language by working for a short time each day rather than one long session each week, so each day look at the vocabulary and listen to the pronunciation video before doing just one worksheet and playing a game. This means that there will be enough material for you to use over several days, so your kid will be able to really learn the vocabulary.