Noun
びーだま
ビーだま
ビー玉をつかってゲームをしましょう。
Let’s play a game that uses marbles.
アメリカではまいとし一月にビー玉をつかったゲームが上手なフランス人がつどうコンテストがあります。
In America, there is a contest every January where French people who are good at marbles gather.
かれは、けっこんのあかしに一つぶのビー玉をくれた。
He gave me a single marble as proof of our marriage.
When you see a katakana word, it's a safe bet that it is a foreign loan word from somewhere else. This one's interesting, because it combines katakana and kanji! The first marble came to Japan from Portugal, so the ビー part of the word is short for "vidro," which means "glass" in Portuguese. Anyway, don't get thrown off by that ビー. Maybe just imagine that your favorite marble is black and yellow like a 🐝
If you know katakana as well as the reading that you learned when you learned the kanji 玉, you should be able to read this. Just watch out for the rendaku.