私のむすめたち

[ Good :) ]

KennedyはようちえんをはべることでKaydenはほいくえんをはべります.

【Kennedyはようちえんにいっていて、Kaydenはほいくえんにいっています.】

[ We say "がっこうにいっています" if we usually go to school. I will break down the sentence for you.

がっこう = school (In your daughters' case, it should be ようちえん or ほいくえん.)

に = to ( "に" is one of Japanese particles that express motion towards a location. It is like a preposition "to" in English )

いっています = It's originally from the dictionary form いく, which means "to go". We often use "～ています" form to express that we do something regularly. *We use "～ています" as a continuous form as well. ]

Kennedyはテレビをみて遊びます.

[ Good :) ]

Kaydenはとてもわかいから、あんまり趣味がありません.

【Kaydenはちいさすぎるから、あんまり趣味がありません.】

[ We say ちいさすぎる, which literally means "too small". The original adjective is "ちいさい". ]

★ちいさい娘さんがふたりいると、たのしいですね。にほんご、じょうずにかけていますよ :)

私のむすめたち

I wasn't sure what exactly you wanted to say by "はべることで" and "はべります” so I just corrected as " starting Youchien/Hoikuen" but if this wasn't what you meant then please let me know.