There are many beaches in West Maui.  They're all different.  We choose based on what we feel like doing that day.  We've found that we like to go early, so we are through by noon or soon after.  It gets hot out there after noon, and sometimes too crowded for our tastes.  We like to eat lunch out, so we do that, and then do non-beach stuff in the afternoon.  The first beach is less than 50 steps from our lanai across the grass, then we will head north.

Kahana Beach
Convenient.  Nice for morning and evening walks and hanging around on the beach.  The reef is quite a ways out where there is good snorkeling straight out from the south side of Valley Isle.  I've seen turtles, octopus, eels along with the usual reef fish.    It's shallow most of the way out there.  During low tide you can scratch your tummy if you're not careful.  Also some nice coral formations if you can find them.  For playing in the water, it's best in front of the Kahana Sands, which is the next resort south.

Napili
Very nice sandy swimming beach for families and children.  Good for playing in the waves in middle of beach.  Calm for kids and more timid souls on north end by restaurant.  Fairly good snorkeling on both north and south edges of the bay.  There is also a reef in the middle which is ok for snorkeling.

Kapalua Beach
Pretty white-sand crescent beach.  Great for kids.  One of the safest year round swimming spots north of Lahaina.  Great snorkeling on North end.  You can also rent boards and stuff on the north end.  We rented a see thru board, and I got Karen out in the water to see some of the things I do.  (Karen doesn't swim)
Best time to go is 9 or 10 in the morning.  Sometimes have trouble finding a parking spot.

Fleming Beach on Honokahua Bay
This one is great for surfing, boogie boarding and body surfing.  Shallow sandy bottom extends quite a ways out.  Local surfers play on waves on north end which, when water is too calm for the surfers, is good for snorkeling.  Besides being fun, the waves can be dangerous.  I have been body slammed into the sand by the waves several times, and that is no fun.  There have been numerous injuries here, so be careful!!  There is a lifeguard.  The Ritz Carlton has an outdoor restaurant on the south end.  Karen and I sometimes have lunch here after we're done playing in the waves.

Slaughter House on Mokuleia Bay
No, the waves don't slaughter you here, there used to be a slaughter house on the ridge above the bay.  After parking on the road (don't leave anything valuable in your car) and a long walk down a stairway which used to be a rocky muddy path, you get down to the beach.  It is beautiful and small.  Usually good for body surfing and boogie boarding, or just hanging around.  This is an excellent snorkeling spot, and you can even snorkel around the north end to Honolua bay which comes next.  This beach can really change.  On one trip Karen and I played on the sandy beach here, then went over to Molokai for four days.  When we came back we didn't think we were in the same place.  There was no sand, only rocks and big boulders.  The ocean took our nice sandy beach.  So, there might be sand, and there might be only rocks and boulders.

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