Is there a Jewish way to observe Memorial Day?
As a modern American holiday, and a federal and civil holiday, Jewish texts do not prescribe particular observance to this day. The question you pose is a great one, though, as it opens up the conversation on how to bring our Judaism to all aspects of our life, including those that are not inherently Jewish.
Simply because there is no one prescribed way to observe Memorial Day in this context does not mean there aren’t many meaningful ways to commemorate it in light of our heritage and tradition, and to imbue the holiday with Jewish meaning. Several values of great importance in Judaism come into play in our observance of Memorial Day—primarily the value of community and the value of remembrance.
We believe that those who passed away live on through our memories of them. By mentioning their names and by sharing stories of their lives, we not only keep their memory alive but actually add life to their lives. In other words, when we remember them they live on in us. We do this in a Jewish context on the Yahrzeit—yearly, on the date of a person’s passing, and several times a year in a special service in the synagogue called Yizkor, or Remembrance. On Memorial Day we might find ways to remember the departed both within the Jewish community and as part of the wider community.
In the past, some synagogues had the practice of reciting the names of synagogue members who died while in military service on the Shabbat prior to Memorial Day. In some places the rabbi would give a sermon on the topic of the holiday. In some places the local chapter of Jewish War Veterans would hold a service. These traditions are becoming less common but are still practiced in some synagogues. An alternative way to remember the dead within the community might be to sponsor a kiddush following services on the Shabbat of Memorial Day in honor of our soldiers who died while in the service. Such a Kiddush could be an opportunity to share stories of their lives. Another way might be to include the names of the departed and a few words in the synagogue newsletter.
Outside of the synagogue, some congregational youth groups go out to the cemetery and plant flags for Memorial Day. Some chapters of JWV participate in Memorial Day parades. Observing Memorial Day as part of the wider community can be very powerful. One may choose to participate in Memorial Day parades, attend a memorial service or visit the cemetery. 
All of these are very appropriate ways to honor the day. Judaism places great value on experiencing life as part of the community. When we participate in Memorial Day events we are taking our place as part of the fabric of American life, and by doing so we come together as one community to remember and honor those who are no longer among us.
Rabbi Eliana Jacobowitz serves Temple B’nai Brith in Somerville, an independent egalitarian congregation with historical roots in the Conservative movement.