diff --git a/index.html b/index.html
index 8fcfeff..101bd67 100755
--- a/index.html
+++ b/index.html
@@ -312,11 +312,11 @@ <h3 class="text-center">Class Milestones - Important Dates</h3>
             <div class="col-lg-8 col-lg-offset-2 col-xs-10 col-xs-offset-1">
                 <p>Keep in mind the <a href="https://www.bu.edu/reg/calendars/semester/" target="_blank">Official Semester Dates</a>.</p>
                 <ul>
-                    <li>January 31, last day to add (any) class</li>
+                    <!-- <li>January 31, last day to add (any) class</li> -->
                     <!-- <li>February 9th, select a project</li> -->
                     <!-- <li>February 19th, decide the semester project (which you have discussed in OH)</li> -->
-                    <!-- <li>February 28th, submit your project proposal</li> -->
                     <li>February 22, last day to drop (without a "W")</li>
+                    <li>February 23, submit your project proposal</li>
                     <!-- <li>March 28th, submit your mid-semester progress report</li> -->
                     <li>March 29, last day to drop (with a "W")</li>
                     <!-- <li>April 23rd, submit your draft project presentation for review prior to presentation</li> -->
@@ -512,7 +512,7 @@ <h3 class="post-subtitle">
                         (run length encoding), hash joins, index joins, sort-merge joins, invisible joins, star schema
                         <h4>Readings</h4>
                         <ul class="mylist">
-                            <!-- <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class7.pdf">Slides</a> </li> -->
+                            <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class6-Student-Presentation-1.pdf">Slides</a> </li>
                             <li><strong>(P)</strong> <a href="https://dl.acm.org/citation.cfm?doid=1376616.1376712">Column-Stores vs. Row-Stores: How Different Are They Really?</a>, SIGMOD 2008 (paper for <strong class="red"><script type="text/javascript">document.write("REVIEW R"+(review++)); </script></strong>) </li>
                             <li>(B) <a href="https://dl.acm.org/citation.cfm?id=1083658">C-Store: A Column-oriented DBMS</a>, VLDB 2005</li>
                         </ul>
@@ -578,7 +578,7 @@ <h3 class="post-subtitle">
                         <strong>Concepts</strong>: key-value stores, point queries, blind updates, read-modify-write, on-line transaction processing (OLTP), on-line analytical processing (OLAP), locality, immutable file, mutable file, append-only systems, in-place updates
                         <h4>Readings</h4>
                         <ul class="mylist">
-                            <!-- <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class17.pdf">Slides</a> </li> -->
+                            <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class8-Student-Presentation-2.pdf">Slides</a> </li>
                             <li><strong>(P)</strong> <a href="https://dl.acm.org/citation.cfm?id=3196898">FASTER: A Concurrent Key-Value Store with In-Place Updates</a>, SIGMOD 2018 [<a href="https://www.youtube.com/watch?v=68YBpitMrMI" target="_blank">conf. present. video</a>] (paper for <strong class="red"><script type="text/javascript">document.write("REVIEW R"+(review++)); </script></strong>)</li>
                             <li> (B) <a href="https://dl.acm.org/citation.cfm?id=2610502">H2O: A Hands-free Adaptive Store</a>, SIGMOD 2014</li>
                             <li> (B) <a href="https://www.cidrdb.org/cidr2011/Papers/CIDR11_Paper25.pdf">Towards a One Size Fits All Database Architecture</a>, CIDR 2011</li>
@@ -609,7 +609,7 @@ <h3 class="post-subtitle">
 
                         <h4>Readings</h4>
                         <ul class="mylist">
-                            <!-- <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class11.pdf">Slides</a> </li> -->
+                            <li><a target="_blank" style="font-size:18px; text-decoration: underline;" tabindex="-1" href="./slides/CAS-CS561-Class9.pdf">Slides</a> </li>
                             <li>(B) <a href="https://arxiv.org/abs/1812.07527">LSM-based Storage Techniques: A Survey</a>, arXiv 2018</li>
                             <!-- <li class="tech-question"><font
                          color="#cc0000"><strong>Technical
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