I'd absolutely pitch, Maria. Board books might be a hard sell, but so is anything in publishing, really! I'd do so in the same way as a picture book, taking extra care with the pitch. If it helps, I have one (text only) out on (agented) sub right now. That said, I definitely recommend following Vijaya's advice about keeping an eye out for opportunities.
Vijaya, my son LOVES Ten Easter Eggs. We must have read it about a hundred times by now. It's such a clever concept, and so beautifully executed!